Value Of Cone Beam Computed Tomography Research Articles

Evaluation of children's oral diagnosis and treatment using imaging examination using AI based Internet of Things.

Although cone beam computed tomography (CBCT) plays an important role in the diagnosis and treatment of oral diseases, its image segmentation method needs to be further improved, and there are still objections about the clinical application effect of general anesthesia (GA) on children's dental fear (CDF). This study aimed to investigate the application value of CBCT based on intelligent computer segmentation model in oral diagnosis and treatment of children in the context of biomedical signals, and to analyze the alleviating effect of GA on CDF. Based on the regional level set (CV) algorithm, the local binary fitting (LBF) model was introduced to optimize it, and the tooth CBCT image segmentation model CV-LBF was established to compare the segmentation accuracy (SA), maximum symmetric surface distance (MSSD), average symmetric surface distance (ASSD), over segmentation rate (OR), and under segmentation rate (UR) between these model and other algorithms. 82 children with CDF were divided into general anesthesia group (GAG) (n= 38) and controls (n= 44) according to the voluntary principle of their families. Children in GAG were treated with GA and controls with protective fixed intervention. Children's fear survey schedule-dental subscale (CFSS-DS) and Venham scores were counted before intervention in the two groups. CFSS-DS scores were recorded at 2 hours after intervention and after recovery in children in GAG. CFSS-DS and Venham scores were performed in all children 1 week after surgery. The results showed that the S⁢A value of CV-LBF algorithm was higher than that of region growing algorithm (P< 0.05). OR, UR, MSSD, and ASSD values of CV-LBF algorithm were evidently lower than those of other algorithms (P< 0.05). CFSS-DS scores were lower in GAG than in controls 2 hours after intervention and at return visits after 1 week of intervention (P< 0.001), and Venham scores were lower in GAG than in controls after intervention (P< 0.001). After intervention, the proportion of children with Venham grade 0, 1, 2, and 3 was obviously higher in GAG than in controls (P< 0.001), while the proportion of children with Venham grade 4 and 5 was clearly higher in controls than in GAG (P< 0.001). The results revealed that the computer intelligent segmentation model CV-LBF has potential application value in CBCT image segmentation of children's teeth, and GA can effectively alleviate anxiety of children with CDF and can be used as biomedical signals.

Deep learning to assess bone quality from panoramic radiographs: the feasibility of clinical application through comparison with an implant surgeon and cone-beam computed tomography.

Bone quality is one of the most important clinical factors for the primary stability and successful osseointegration of dental implants. This preliminary pilot study aimed to evaluate the clinical applicability of deep learning (DL) for assessing bone quality using panoramic (PA) radiographs compared with an implant surgeon's subjective tactile sense and cone-beam computed tomography (CBCT) values. In total, PA images of 2,270 edentulous sites for implant placement were selected, and the corresponding CBCT relative gray value measurements and bone quality classification were performed using 3-dimensional dental image analysis software. Based on the pre-trained and fine-tuned ResNet-50 architecture, the bone quality classification of PA images was classified into 4 levels, from D1 to D4, and Spearman correlation analyses were performed with the implant surgeon's tactile sense and CBCT values. The classification accuracy of DL was evaluated using a test dataset comprising 454 cropped PA images, and it achieved an area under the receiving characteristic curve of 0.762 (95% confidence interval [CI], 0.714-0.810). Spearman correlation analysis of bone quality showed significant positive correlations with the CBCT classification (r=0.702; 95% CI, 0.651-0.747; P<0.001) and the surgeon's tactile sense (r=0.658; 95% CI, 0.600-0.708, P<0.001) versus the DL classification. DL classification using PA images showed a significant and consistent correlation with CBCT classification and the surgeon's tactile sense in classifying the bone quality at the implant placement site. Further research based on high-quality quantitative datasets is essential to increase the reliability and validity of this method for actual clinical applications.

Evaluation of Canal-centering Ability and Apical Transportation of Hyflex-EDM, OneShape, WaveOne Gold, and Reciproc Files: An Ex Vivo Study.

To evaluate and compare canal-centering ability (CCA), canal transportation (CT), and dentinal crack formation by using Hyflex-electrical discharge machining (EDM), OneShape, WaveOne Gold, and Reciproc single file system in the mesiobuccal root of maxillary first molar at coronal, middle, and apical third using cone-beam computed tomography (CBCT) and scanning electron microscopy (SEM). Mesiobuccal roots of 120 freshly extracted maxillary molar teeth were divided into four experimental groups; Hyflex-EDM, OneShape, WaveOne Gold, and Reciproc (n = 30/group). Preinstrumentation scanning was done using CBCT for all samples at coronal one-third (4 mm), middle one-third (8 mm), and apical one-third (12 mm). After cleaning and shaping with standard irrigation protocol, the specimens were again scanned. Canal-centering ability and CT were calculated using pre- and postinstrumentation CBCT values. A scanning electron microscope was used to identify dentinal crack formation. No significant difference was found for CCA by any of the systems at coronal, middle, and apical third, respectively. However, OneShape was found to have better CCA at the coronal third and WaveOne Gold at the middle and apical third. There was a significant difference in canal transportation at the apical third (p = 0.004) with WaveOne Gold having the least CT followed by Reciproc at the apical third. OneShape resulted in more dentinal cracks in the coronal and middle thirds. Also, Hyflex-EDM was better in the apical third. No difference in CCA was observed between the groups. The lowest values for CT were obtained for WaveOne Gold (similar to Reciproc) whereas both rotary files showed higher values for CT. Also, OneShape showed the most dentinal at all levels. Furthermore, Hyflex-EDM and WaveOne Gold produced the least dentinal cracks at all levels. Given that the Reciprocating file system had the least CT and least dentinal cracks, the clinical success rate of root canal treatment (RCT) with the Reciprocating file system can be a better choice to improve the longevity of root canal-treated teeth.

Clinical Effect of Platelet-Rich Fibrin Combined with BIO-GENE Artificial Bone Meal in Bone Defects After Jaw Cyst Surgery.

To compare the clinical repair effects of leaving the defect empty and using Platelet-Rich Fibrin (PRF) combined with BIO-GENE artificial bone powder in patients with bone defects 6 months after jaw cystectomy. From June 2021 to June 2022, 70 patients who were admitted to the Department of Stomatology, Affiliated Hospital of Yanbian University, and were diagnosed with jaw cysts postoperatively were selected. All of the patients were divided into two groups according to random method, among which 35 patients who underwent cystectomy alone were recorded as group A, which served as blank control; 35 patients who underwent cystectomy and PRF combined with BIO-GENE artificial bone meal repaired bone defects during the same period were recorded as group B. 3D Slicer 5.0.3 software was used to reconstruct Cone Beam Computed Tomography (CBCT) after operation. In this study, the preoperative and postoperative CBCT data of the patients were analyzed using 3D Slicer 5.0.3 software in DICOM format to calculate the cleft volume before surgery and the newly formed bone volume after surgery. The osteogenesis rate was measured based on these calculations.The bone formation percentage in the bone defect area was recorded at 6 months, and the clinical curative effects of the two groups were compared. After 6 months of surgery, the patients showed varying degrees of restoration in the jaw cyst area.The osteogenesis rate at 6 months in group A was 76.06±13.38%, while group B had a rate of 92.87±5.72%.The CBCT values in group B were higher than those in group A at 6 months post-surgery (P<0.05), t=-6.84.Group A and Group B showed a statistically significant difference. Compared with simple cystectomy, PRF combined with BIO-GENE artificial bone powder has a better effect on the speed of bone repair after cystectomy within 6 months and provides more favorable effects for the repair of postoperative dentition defects, and provides support to repair teeth after defects such as dental implants.

Added Value of Cone-Beam CT to Identify Arterial Supply during Genicular Artery Embolization for Knee Osteoarthritis

PurposeTo evaluate if the addition of cone-beam computed tomography (CT) to digital subtraction angiography (DSA) improves the identification of the genicular arteries during genicular artery embolization (GAE) for knee pain secondary to osteoarthritis (OA). Materials and MethodsThis single-center study retrospectively analyzed 222 patients who underwent GAE for painful knee OA between May 2018 and April 2022. Intraprocedural cone-beam CT and DSA images were reviewed independently by 2 sets of interventional radiologists. DSA was performed for all patients. Technically adequate cone-beam CT was available for 205 patients (92.3%). The presence of the genicular arteries identified by cone-beam CT and DSA was compared using Φ coefficients. Embolization targets identified by both cone-beam CT and DSA were evaluated against those identified by DSA alone. ResultsGenicular arteries with the highest concordance between cone-beam CT and DSA were the inferior lateral (196 vs 198; Φ = 0.3530; P < .0001), superior lateral (197 vs 200; Φ = 0.3060; P < .0001), and superior medial genicular (186 vs 161; Φ = 0.2836; P < .0001) arteries. Cone-beam CT demonstrated higher rates of detection of the inferior medial (195 vs 178; Φ = 0.04573; P = .5150) and median genicular arteries (200 vs 192; Φ = 0.04573; P = .5150). Meanwhile, genicular arteries less frequently identified by cone-beam CT were the descending genicular (197 vs 200; Φ = −0.03186; P = .6502), superior patellar (175 vs 184; Φ = 0.1332; P = .0569), and recurrent anterior tibial (156 vs 186; Φ = 0.01809; P = .7969) arteries. Cone-beam CT in combination with DSA identified 13.4% (372 vs 328) more targets compared to DSA alone. ConclusionsBased on the results of the current study, cone-beam CT serves as a valuable adjunct for visualizing the genicular arteries during GAE, and together with DSA, it identifies more potential embolization targets.

Bone Mineral Density through DEXA and CBCT: A Systematic Review with Meta-Analysis

Dual-energy X-ray absorptiometry is used to determine bone density in several pathologies, namely osteoporosis and fracture risk in post-menopausal women. The aim of this study was to identify, appraise and synthesize all available evidence about the correlation between Dual Energy X-ray Absorptiometry (DEXA) and Cone Beam Computed Tomography (CBCT) techniques through a systematic review. A systematic literature search was conducted in the following databases: PubMed via MEDLINE, Cochrane Library, EMBASE and Web of Science Core Collection, along with several sources of grey literature. The Cochrane Risk of Bias Tools were used to perform the qualitative assessment of the selected studies. A total of 913 articles were initially scrutinized and 11 were included for qualitative analysis, of which 3 were included in a meta-analysis. Most of the included studies revealed a low risk of bias (7 out of 11). A strong correlation (min r = 0.46 max r = 0.62) between DEXA and CBCT values were found. Thus, opportunistic CBCT scans may be used to assess the bone mineral density and fracture risk, improving the ability to track disease progression and providing better care.

Vitamin D, Cholesterol, and DXA Value Relationship with Bimaxillary Cone Beam CT Values.

We evaluated the correlation that Vitamin D (Vit D), cholesterol levels, and T- and Z-scores of dual-energy X-ray absorptiometry (DXA) scans have with cone beam computed tomography values assessed in the anterior and posterior regions of maxillary and mandibular jaws. In total, 187 patients were recruited for this clinical study. Patients' ages ranged between 45 and 65 years. Patients with valid DXA results, serum Vit D and cholesterol levels, and no evidence of bone disorders in the maxilla or mandibular region were included in the study and grouped in the control (non-osteoporosis) and case (osteoporosis) groups. Patients with a history of medical or dental disease that might complicate the dental implant therapy, chronic alcohol users, and patients who took calcium or Vit D supplements were excluded. The outcome variables assessed in the investigation were Vit D, cholesterol, Z-values, and cone beam computed tomography values. Regarding the case group, a significant (p < 0.05) inverse relationship was observed between Vit D and cholesterol. Although insignificant (p > 0.05), a positive relationship was found between Vit D and the cone beam computed tomography values in all regions of the jaws, except the mandibular posterior region (p < 0.05). Pearson correlation analysis was carried out. Vit D and cholesterol showed a statistically insignificant (p > 0.05) negative association with the cone beam computed tomography values in all regions of the jaws. However, the Z-values were highly correlated with the cone beam computed tomography values in all regions of the jaws (r > 7, p < 0.05). Vit D, cholesterol levels, and Z-values in women and men from young adulthood to middle age (45-65) were related with the cone beam computed tomography values of the jaws.

In Vitro Diagnostic Accuracy and Agreement of Dental Microscope and Cone-Beam Computed Tomography in Comparison with Microcomputed Tomography for Detection of the Second Mesiobuccal Canal of Maxillary First Molars.

Objectives The percentage of failure of endodontically treated maxillary molars is relatively high; one main reason is that the second mesiobuccal canal (MB2) is missing. Some techniques have been proposed for detection of the MB2. This study was aimed at assessing the diagnostic accuracy and agreement of the dental microscope and cone-beam computed tomography (CBCT) in comparison with microcomputed tomography (micro-CT) for detection of the MB2 of maxillary first molars in vitro. Materials and Methods This in vitro, experimental study evaluated 71 permanent maxillary first molars that were stored in 100% humidity at room temperature. The teeth were mounted in 9 silicone dental arches to the level of their cementoenamel junction (8 teeth in each arch). The blocks underwent CBCT in a XG3D scanner. Access cavity was then prepared, and the teeth were inspected by a surgical microscope for negotiation of the MB2. Also, micro-CT images were obtained from the teeth to serve as the gold standard. CBCT and micro-CT images were observed by two examiners twice with a 2-week interval. Results The frequency of the MB2 detected by dental microscope was significantly lower than micro-CT (P < 0.001) and CBCT (P = 0.008); no significant difference existed between micro-CT and CBCT in this respect. The sensitivity, specificity, positive predictive value, and negative predictive value of CBCT for detection of MB2 were 92.6%, 100%, 100%, and 81%, respectively. Conclusion CBCT is superior to the dental microscope for detection of the MB2 of maxillary first molars and can be used for this purpose in the clinical setting with adequate accuracy.

Diagnostic value of CBCT in Chinese children with adenoid hypertrophy.

ObjectiveThe main objectives of the study were to investigate the reliability and accuracy of cone‐beam computed tomography (CBCT) in the diagnosis of adenoid hypertrophy in Chinese children and to evaluate its value in clinical diagnosis.MethodsFrom January 2019 to January 2020, 300 children with sleep snoring in Xinhua Hospital Affiliated to Medical College of Shanghai Jiaotong University were retrospectively studied. All patients underwent nasopharyngoscopy (NE) and CBCT scanning. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of CBCT were determined according to the diagnostic criteria of NE, and the consistency between CBCT and NE was evaluated.ResultsThe clinical study of 300 children patients found that compared with NE, CBCT had a sensitivity of 87.3%, specificity of 89.2%, the positive predictive value of 93.20%, the negative predictive value of 80.5%, the positive likelihood ratio of 8.08, the negative likelihood ratio of 0.14, and Kappa value of .748.ConclusionCBCT is a reliable and accurate tool for the diagnosis of adenoid hypertrophy and can be used as an alternative examination method for children with contraindications or intolerance during NE.Level of Evidence4.

Correlation among alveolar bone assessments provided by CBCT, micro-CT, and 14 T MRI.

The aim of this study was to evaluate bone mineral adipose tissue (BMAT) volume in 21 alveolar bone specimens, as determined by 14 T MRI, and correlate them to the radiodensity values obtained pre-operatively of regions of interest (ROIs) by cone beam computed tomography (CBCT), and to the bone-volume-to-tissue-volume ratio values obtained by micro-CT, the gold-standard for morphometric data collection. Partially edentulous patients were submitted to a CBCT scan, and the radiographic bone densities in each ROI were automatically calculated using coDiagnostiX software. Based on the CBCT surgical planning, a CAD/CAM stereolithographic surgical guide was fabricated to retrieve a bone biopsy from the same ROIs scanned preoperatively, and then to orientate the subsequent implant placement. The alveolar bone biopsies were then collected and scanned using the micro-CT and 14 T MRI techniques. Pearson's correlation test was performed to correlate the results obtained using the three different techniques. In the 21 eligible bone specimens (6 females, 15 males), age (mean age 52.9 years), micro-CT, and 14 T MRI variables were found to be normally distributed (p > 0.05). The strongest-and only statistically significant (p < 0.05)-correlation was found between micro-CT and 14 T MRI values (r = 0.943), and the weakest, between 14 T MRI and CBCT values (r = -0.068). The findings suggest that 14 T MRI can be used to evaluate BMAT as an indirect marker for bone volume, and that CBCT is not a reliable technique to provide accurate bone density values.

Cone beam computed tomography for detecting residual stones in percutaneous nephrolithotomy, a randomized controlled trial (CAPTURE) protocol

IntroductionPercutaneous nephrolithotomy (PCNL) is the standard surgical treatment method for large kidney stones. Its aim is to achieve a stone-free status, since any residual fragments (RFs) after PCNL are likely to cause additional morbidity or stone growth. Enhancing intraoperative detectability of RFs could lead to increased stone-free rates and decreased re-intervention rates. Cone beam computed tomography (CBCT) has recently been introduced in urology as a feasible method for intraoperatively imaging RFs. The aim of this trial is to determine the added value of CBCT in percutaneous nephrolithotomy, by measuring differences in stone-related morbidity for patients with procedures in which a CBCT is used versus patients with procedures without the use of CBCT.MethodsThe CAPTURE trial is an investigator-initiated single-center, randomized controlled trial (RCT) in adult patients who have an indication for percutaneous nephrolithotomy. A contemporary percutaneous nephrolithotomy is performed. Once the surgeon is convinced of a stone-free status by means of fluoroscopy and nephroscopy, randomization allocates patients to either the study group in whom an intraoperative CBCT scan is performed or to the control group in whom no intraoperative CBCT scan is performed. The main endpoint is the stone-free status as assessed four weeks postoperatively by low-dose non-contrast abdominal CT, as a standard follow-up procedure. Secondary endpoints include the number of PCNL procedures required and the number of stone-related events (SREs) registered. The total study population will consist of 320 patients that undergo PCNL and are eligible for randomization for an intraoperative CBCT scan.DiscussionWe deem a randomized controlled trial to be the most effective and reliable method to assess the efficacy of CBCT in PCNL. Though some bias may occur due to the impossibility of blinding the urologist at randomization, we estimate that the pragmatic nature of the study, standardized circumstances, and follow-up methods with pre-defined outcome measures will result in a high level of evidence.Trial registrationNetherlands Trial Register (NTR) NL8168, ABR NL70728.042.19. Registered on 15 October 2019. Prospectively registered.

Cone beam computed tomography with oral contrast for accurate diagnosis and surgical planning of pharyngeal leakage and fistula: a case series

ObjectivePharyngocutaneous fistula is one of the severe complications related to head and neck surgeries. Detecting the accurate three-dimensional location of both the fistula and leakage is essential for surgical treatment. Videofluoroscopy is usually used for locating these; however, its imaging is two-dimensional. We evaluated pharyngeal leakage and fistulae using Cone Beam Computed Tomography (CBCT), known for its three-dimensional high spatial resolution imaging, taken in a sitting position, with oral contrast (contrast CBCT). MethodsPharyngeal leakage and fistulae were evaluated in a total of 31 subjects by sequentially performing videofluoroscopy and contrast CBCT. The detection accuracy of videofluoroscopy and contrast CBCT for leakage and fistula, as well as the ability to determine the extent and depth for surgical planning, were investigated and compared. ResultsVideofluoroscopy and contrast CBCT showed suspicious leakage and/or fistula in six and three of the 31 subjects, respectively. Surgical findings revealed the presence of leakage and/or fistula in three of the 31 subjects. The positive predictive values of videofluoroscopy and contrast CBCT were 50% (3/6) and 100% (3/3), respectively. Contrast CBCT provided more precise images, showing the extent and depth of leakage and fistula in three-dimensions. ConclusionThe present study’s results indicate the usefulness of contrast CBCT in terms of accurate diagnosis of leakage and fistula, due to its three-dimensional imaging being performed with the patient in a sitting position. Level of evidence4.

In vitro Comparison of Cone Beam Computed Tomography and Ultrasonography Imaging Methods in the Evaluation of Artificial Mandible Intraosseous Lesions.

Statement of the Problem: Intraosseous lesions of jaws can be imaged by cone beam computed tomography (CBCT) and ultrasonography (USG). The knowledge of imaging features of these two methods about intraosseous jaw lesions is important for dental radiology.Purpose: The aim of this study is to evaluate artificial mandible intraosseous lesions by using CBCT and USG. Materials and Method: In this in vitro study, intraosseous lesions containing water, milk, olive oil, and liver were evaluated in 60 artificial mandibles by using CBCT and USG. Lesion sizes were compared between CBCT and USG. Lesion sizes were measured on the anterior-posterior, bucco-lingual, and superior-inferior sides. Hounsfield unit (HU) values of the lesions in CBCT images were compared between different materials. Echogenicity of the lesions were evaluated in USG images. One sample t and one-way Anova tests were used for the statistical analysis of the study (p< 0.05).Results: In all size measurements of the lesions, mean CBCT values were statistically higher when compared with USG. In CBCT images, statistically difference was found between the HU values of lesions containing olive oil and other lesion contents. In USG images, echogenicity of water, milk and olive oil was found to be anechoic and the echogenicity of liver was found to be hypoechoic.Conclusion: CBCT was found to be more accurate than USG in measurement of the size of mandibular intraosseous lesions. According to the results of our study, it was thought that only oil content could be differentiated by using CBCT HU values. It was found that lesions with liquid and non-liquid contents could be differentiated with their echogenicity difference in USG images.

ACCURACY OF LINEAR MEASUREMENTS OF THIN CORTICAL BONE ON EXPERIMENTAL SURGICAL DEFECTS IN CBCT IMAGES WITH DIFFERENT EXPOSURE PROTOCOLS: AN IN VITRO STUDY

<h3>BACKGROUND</h3> Diagnostic imaging is mandatory for the assessment of osseous defects in the jaws. Traditional imaging has offered much over the decades in the evaluation of these defects but is limited because of its 2D nature. The introduction of cone beam computed tomography (CBCT), a 3D radiographic technique with interactivity, high resolution, and high accuracy, has provided solutions in the evaluation of such lesions <h3>OBJECTIVE(S)</h3> The purpose of this in vitro investigation was to evaluate the accuracy of representation of experimental surgical defects with CBCT using different exposure parameters. Moreover, the study aims to assess the effect of different exposure protocols on the accuracy of representation of experimental surgical defects. <h3>STUDY DESIGN</h3> Surgical defects were prepared in 8 pig jaw mandibular segments. The thickness of the cortical bone around the defects was measured in predetermined areas using the measurement tools of the CBCT software. In total, 48 locations were measured for bone thickness. The pig jaw specimens were imaged with 6 different exposure protocols created by altering voxel size, kilovoltage peak, and milliamperage. The measurements were made by 2 experienced examiners using the original scanner software. The evaluation of the surgical defects was completed in 4 rating sessions; a fifth rating session was included for intraobserver reliability assessment. <h3>RESULTS</h3> There were statistically significant differences in the estimation of cortical bone thickness around experimental surgical defects in certain sites among the variable exposure protocols; however, the differences were too small to be clinically important. The intra- and interobserver reliability values were very high, confirming the diagnostic value of CBCT in different exposure settings. <h3>DISCUSSION/CONCLUSIONS</h3> The accuracy of lineal cortical bone measurements with CBCT was high, even in lower dose protocols, a finding that is in line with the ALADA (as low as diagnostically acceptable) concept.

Synthetic CT generation from CBCT images via unsupervised deep learning

Adaptive-radiation-therapy (ART) is applied to account for anatomical variations observed over the treatment course. Daily or weekly cone-beam computed tomography (CBCT) is commonly used in clinic for patient positioning, but CBCT’s inaccuracy in Hounsfield units (HU) prevents its application to dose calculation and treatment planning. Adaptive re-planning can be performed by deformably registering planning CT (pCT) to CBCT. However, scattering artifacts and noise in CBCT decrease the accuracy of deformable registration and induce uncertainty in treatment plan. Hence, generating from CBCT a synthetic CT (sCT) that has the same anatomical structure as CBCT but accurate HU values is desirable for ART. We proposed an unsupervised style-transfer-based approach to generate sCT based on CBCT and pCT. Unsupervised learning was desired because exactly matched CBCT and CT are rarely available, even when they are taken a few minutes apart. In the proposed model, CBCT and pCT are two inputs that provide anatomical structure and accurate HU information, respectively. The training objective function is designed to simultaneously minimize (1) contextual loss between sCT and CBCT to maintain the content and structure of CBCT in sCT and (2) style loss between sCT and pCT to achieve pCT-like image quality in sCT. We used CBCT and pCT images of 114 patients to train and validate the designed model, and another 29 independent patient cases to test the model’s effectiveness. We quantitatively compared the resulting sCT with the original CBCT using the deformed same-day pCT as reference. Structure-similarity-index, peak-signal-to-noise-ratio, and mean-absolute-error in HU of sCT were 0.9723, 33.68, and 28.52, respectively, while those of CBCT were 0.9182, 29.67, and 49.90, respectively. We have demonstrated the effectiveness of the proposed model in using CBCT and pCT to synthesize CT-quality images. This model may permit using CBCT for advanced applications such as adaptive treatment planning.

Evaluation of the relationship between phantom position and computed tomography dose index in cone beam computed tomography when assuming breast irradiation.

This study aims to investigate the influence of the phantom position on weighted computed tomography dose index (CTDIw) in cone beam computed tomography (CBCT) when assuming breast irradiation. Computed tomography dose index (CTDI) was measured by the x‐ray volume imaging of CBCT using parameters for image‐guided radiation therapy (IGRT) in right breast irradiation. The measurement points of CTDI ranged from 0 (center) to 16 cm in the right–left (RL) direction, and from 0 (center) to 7.5 cm in the anterior–posterior (AP) direction, which assumed right breast irradiation. A nonuniform change exists in the relative value of CTDIw when the phantom deviated from the isocenter of CBCT. The CTDIw was ~30% lower compared with the value at the isocenter of CBCT when the phantom deviated 7.5 and 16 cm at the AP and RL directions, respectively. This study confirmed the influence of the phantom position on the CTDI values of CBCT. The CTDI measured at the isocenter of CBCT overestimates that measured at the irradiation center of the breast.

Diagnosis of cracked teeth using cone-beam computed tomography: literature review and clinical experience

Cone-beam computed tomography (CBCT) has been widely used in diagnosis of vertical root fractures (VRFs) in recent years. According to the American Association of Endodontists (AAE) classification, there are five types of cracked teeth and VRF is one of them. Due to the variability and overlapping of the cracks and fractures, some narrow fractures on the roots of VRFs could not be detected by CBCT, and some wide cracks on the crown of cracked teeth could be detected by CBCT. In this review, we firstly discussed the value of CBCT in the diagnosis of the AAE five types of cracked teeth and presented CBCT manifestations of some typical cases. Secondly, we summarized the factors influencing the diagnosis of cracks/fractures using CBCT, namely, CBCT device-related factors, patient-related factors, and evaluator-related factors. The possible strategies to improve the diagnostic accuracy in the clinic practice are also discussed in this part. Finally, we compared the differences of root fractures with lateral canals and external root resorption on CBCT images.

Clinical and Radiographic Gingival Thickness Assessment at Mandibular Incisors: an Ex Vivo Study.

Gingival phenotype influences the outcomes of various dental procedures. The objective of the current study was to assess the agreement between various clinical and radiographic methods for evaluating gingival thickness. This ex-vivo study evaluated gingival thickness on 20 porcine cadavers. Gingival thickness was assessed at both central mandibular incisors with: a) trans-gingival probing with a standard periodontal probe (PB); b) trans-gingival probing with a stainless steel acupuncture needle (AN); c) ultrasound device (USD); and d) Cone Beam Computed Tomography (CBCT). Intra-examiner reproducibility and method error were also evaluated. Trans-gingival measurements with the standard PB and the AN were found to be almost identical in gingival thickness assessment (mean GT 1.11 mm vs 1.14 mm for the left incisor and mean GT 1.12 mm vs 1.11 mm for the right incisor, respectively). USD and CBCT yielded values that were statistically significantly higher than AN. Both USD and CBCT values were higher than PB, but this difference was statistically significant only for the left central incisor. Finally, USD values exceeded CBCT measurements, but this difference was not statistically significant. There was no evidence of systematic differences between the repeated CBCT measurements (p = 0.06 for the left incisor and p = 0.55 for the right incisor). CBCT measurements proved to be highly repeatable and comparable to the USD measurements, while there were some indications that both CBCT and USD measurements were systematically higher than either PB or AN.

Accuracy of panoramic radiography for degenerative changes of the temporomandibular joint

Background:Temporomandibular joint (TMJ) morphologies are complex, and changes in joint components have been studied extensively. TMJ conditions have many different etiologies, appearances, and relevant clinical significance.Objective:The objective of this study was to evaluate the concordance of the diagnosis of degenerative changes in the TMJ in panoramic radiographs.Materials and Methods:Cone beam computed tomography (CBCT) was used as a reference standard. Images of 84 patients (168 TMJs), 61 females (72.6%) and 23 males (27.4%) with an average age of 47.4 years, were evaluated by three radiologists who established the presence or absence of degenerative changes in the jaw heads. The data were collected and organized in a spreadsheet. Concordance between evaluators was analyzed using agreement percentages, statistical κ, and confidence intervals. In the analysis of compliance with CBCT, sensitivity, specificity, predictive positive and negative values, and probabilities of false positives and negatives were also calculated. All inferential tests were performed with a 5% significance level.Results:The percentage of agreement among raters in panoramic radiographs ranged from 66.7% to 82.9%, considered mild to moderate. Correlation between radiographic and tomographic images ranged from 45.5% to 64.9% in the inter-evaluator reviews, representing a very mild agreement. Sensitivity ranged from 28.6% to 58.7% and specificity from 66.7% to 100.0%. Positive predictive value ranged from 77.1% to 100.0%; the negative predictive value was lower, ranging from 32.2% to 54.8%. The probability of false negatives was higher than that of false positives, ranging from 45.2% to 67.8%.Conclusion:The rater did not reach acceptable diagnosis levels.

Kist Enükleasyonu Sonrası Oluşan Kemik Rejenerasyonunun Radyolojik Değerlendirmesinde Konik Işınlı Bilgisayarlı Tomografi ile Panoramik Radyografinin Karşılaştırmalı Olarak İncelenmesi

Objective: The aim of this study is to compare the panoramic radiography and cone-beam computed tomography (CBCT) in the evaluation of bone healing after the enucleation of odontogenic cysts. Methods: Pre-operative and post-operative clinical and radiological data of patients who were successfully treated with enucleation between 01/01/2013 and 01/03/2017 with 1-year follow-up were retrieved from the archives and evaluated retrospectively. The panoramic radiographs and CBCT sections were transferred into a computer program and pre-operative and post-operative measurements were performed on the computer program. The manual segmentation method was used in the volume measurement in CBCT sections. An area index was calculated by multiplying the highest vertical and widest horizontal dimension of the cystic lesion on the panoramic radiography. Results: Twelve patients included in the study. Eight patients were male and 4 of them were female. The mean age was 45. The volume of the defect at post-operative 1-year control decreased by 83.05% on average. The area measurement showed a decrease of 38.79% at postoperative 1-year control. The volume of the cystic cavities in tomographic sections and cystic area on panoramic radiographs were significantly reduced at the end of 1-year follow-up (p&amp;lt;0.05). There was a significant and moderate positive relationship between the post-operative measurement values of CBCT and OPG (p=0.021, r=0.655). Conclusion: Panoramic radiography can be used as effective as CBCT to monitor spontaneous bone regeneration after the enucleation of jaw cysts.