Assessment of accuracy and reproducibility of cephalometric identification performed by 2 artificial intelligence-driven tracing applications and human examiners.

OBJECTIVE: To assess the accuracy and reproducibility of cephalometric landmark identification performed by 2 artificial intelligence (AI)-driven applications (CefBot and WebCeph) and human examiners. STUDY DESIGN: Lateral cephalometric radiographs of 10 skulls containing 0.5 mm lead spheres directly placed at 10 cephalometric landmarks were obtained as the reference standard. Ten radiographs without spheres were obtained from the same skulls for identification of cephalometric points performed by the AI applications and 10 examiners. The x- and y-coordinate values of the cephalometric points identified by the AI applications and examiners were compared with those from the reference standard images using one-way analysis of variance and the Dunnet post-hoc test. The intraclass correlation coefficient (ICC) was used to evaluate reproducibility. Mean radial error (MRE) in identification was calculated with respect to the reference standard. Statistical significance was established at P < .05. RESULTS: Landmark identification by CefBot and the examiners did not exhibit significant differences from the reference standard on either axis (P > .05). WebCeph produced a significant difference (P < .05) in 4 and 6 points on the x- and y-axes, respectively. Reproducibility was excellent for CefBot and the examiners (ICC ≥ 0.9943) and good for WebCeph (ICC ≥ 0.7868). MREs of CefBot and the examiners were similar. CONCLUSION: With results similar to those of human examiners, CefBot demonstrated excellent reliability and can aid in cephalometric applications. WebCeph produced significant errors.

Tridimensional assessment of the mandibular angle in patients with different skeletal patterns by cone-beam computed tomography scans: a retrospective study.

BACKGROUND: Since the muscles of chewing are involved in the region of the mandibular angle, important structures in surgical and orthodontic procedures, to study its morphological aspects and the possible influence of different patterns of skeletal development would be of interest. Thus, this study aimed to assess the influence of patient characteristics - such as sex, skeletal malocclusion (Class I, Class II, and Class III) and facial type (brachycephalic, mesocephalic, and dolichocephalic) - on the width, height, thickness, and volume of the mandibular angle, using cone-beam computed tomography (CBCT) scans. METHODS: CBCT scans were assessed - 144 men and 154 women, total of 298 - and classified according to skeletal patterns (skeletal malocclusions and facial types). Width, height, and thickness of the mandibular angle were measured using OnDemand 3D software. The volumetric measures of the mandibular angle were obtained using the ITK-SNAP software. Analysis of Variance (multiway ANOVA) with Tukey's post-hoc test compared the data, with a 5% significance level. RESULTS: Among the factors studied, sex significantly influenced all the analyzed variables (height, width, thickness, and volume of the mandibular angle) (p < 0.05); in general, male individuals presented higher values than females. In some cases, the skeletal malocclusion and facial type factors influenced only the width and height variables (p < 0.05); in general, the Class III and dolichocephalic individuals presented higher values in relation to the other types of skeletal malocclusions and facial types. CONCLUSIONS: Variations in the craniofacial growth pattern, considering the different skeletal malocclusions and facial types, had some influence in the width and height dimensions of the mandibular angle. Furthermore, sex influenced all the studied variables.

Revisiting dynamic range and image enhancement ability of contemporary digital radiographic systems-part 2: a subjective assessment.

OBJECTIVE: To assess the subjective image quality of original and manually enhanced radiographs acquired at different X-ray exposure times and using different digital systems. METHODS: A total of 500 radiographs obtained under 10 exposure times, 5 digital systems, and 2 enhancement conditions were assessed by 5 observers, who were asked to categorize each radiograph into acceptable or unacceptable. A radiograph was considered to be acceptable when at least four out of five observers found it acceptable. Descriptive analysis was used to summarize the outcomes and compare the subjective image quality of original and manually enhanced digital radiographs among different X-ray exposure times and digital systems. RESULTS: Express had six exposure times producing acceptable original images within a range from 0.063 to 0.4 s, followed by Digora Toto, which had five within a range from 0.063 to 0.32 s, Digora Optime, which had four within a range from 0.063 to 0.2 s,and SnapShot and VistaScan, which had 2 (0.2 and 0.32 s) and 1 (0.63 s), respectively. Image enhancement turned unacceptable images into acceptable ones in four digital systems: SnapShot at three exposure times, Digora Toto at two exposure times, Express at one exposure time, and VistaScan at four exposure times. CONCLUSION: Image enhancement based on brightness and/or contrast adjustments may be necessary to reveal the useful dynamic range of some digital radiographic systems and PSP-based systems may not necessarily have a wider range than sensor-based systems.

Combined Use of 2 Cone-beam Computed Tomography Scans in the Assessment of Vertical Root Fracture in Teeth with Intracanal Material.

INTRODUCTION: The purpose of this preliminary study was to evaluate the diagnostic accuracy of the combined use of 2 cone-beam computed tomographic (CBCT) volumes obtained with the tooth of interest positioned at different orientations in the detection of vertical root fracture (VRF). METHODS: Thirty single-rooted teeth were divided into 2 main groups (n = 15): control and with VRF. The teeth were individually placed in a phantom composed of a human skull and mandible, which was CBCT scanned in 2 spatial orientations: conventional (with the Frankfurt plane parallel to the floor) and angled acquisition (tilted 90° backward). Also, each tooth was scanned with gutta-percha, a metal post, and without any intracanal material. Three oral radiologists individually evaluated the images resulting from conventional acquisition and verified the presence or absence of VRF (conventional CBCT assessment), setting a score on a 5-point scale. Subsequently, the observers evaluated both images resulting from the conventional and angled acquisitions (combined CBCT assessment). The diagnostic values of the conventional and combined assessments were compared using 2-way analysis of variance with the post hoc Tukey test. The significance level was set at 5% (α = 0.05). RESULTS: The combined CBCT assessment showed higher accuracy and sensitivity in the VRF diagnosis of teeth filled with gutta-percha (P < .05). In teeth with a metal post, all diagnostic values were higher in the combined CBCT assessment (P < .05). CONCLUSIONS: This preliminary study suggests that the CBCT-based diagnosis of VRF in teeth with intracanal material was improved when the assessment combines images obtained at 2 orientations.

Assessment of dentists' behaviour on the use of patients' images.

BACKGROUND: Photographs and radiographs are indispensable resources for dental education, research and dissemination of clinical cases in scientific journals. The objective of this study was to evaluate the behaviour of dentists on the use of patients' images. MATERIAL AND METHODS: Fifty-two dentists were interviewed using a semi-structured script containing open-ended questions on the use of patients' images. The answers were analysed using a qualitative-quantitative method of the discourse of the collective subject, and the distribution of the absolute and relative frequency of the answers was presented according to the central ideas obtained from the discourses. RESULTS: The following central ideas on the use of patients' images were identified: (a) purpose: didactic and/or academic; (b) informed consent: verbal or absent when the patient cannot be identified; (c) discussion groups on social media contribute to learning; (d) most dentists would not appreciate and sue the author if they had their own photographs/imaging examinations posted on social media; 5. most dentists received some information on ethical regulations during dental school and state that images can be used with patient authorisation, without identification and for didactic/academic purposes. CONCLUSION: Dentists consider the use of patients' images for didactic and scientific purposes beneficial, request informed consent to share mainly images that reveal the identity and would not appreciate if their personal images were shared without consent.

Radiologic assessment of mandibular third molars: an ex vivo comparative study of panoramic radiography, extraoral bitewing radiography, and cone beam computed tomography.

OBJECTIVES: The aim of this study was to compare the performance of panoramic radiography (PAN), extraoral bitewing radiography (EBW), and cone beam computed tomography (CBCT) in the assessment of mandibular third molars. STUDY DESIGN: PAN and EBW were obtained to visualize 34 third molars. The teeth were evaluated by using PAN and EBW according to their positions, the presence of radiographic signs of proximity of the roots to the mandibular canal, the relationship of the roots to the canal, and the relationship of the second and third molars. Third molar position and root relationship with the canal were also assessed with CBCT. RESULTS: PAN and EBW showed significantly closer relationships compared with CBCT between the tooth and the mandibular canal (P ≤ .002). With regard to all other parameters, no differences were seen between PAN and EBW (P ≥ .072), although EBW, in comparison with PAN, showed a decreased overlap between the proximal surfaces of the second and third molars and a greater trend toward approximating root apices and the canal. CONCLUSIONS: In comparison with PAN, EBW showed a tendency to project the roots closer to the mandibular canal, but there was a decrease in the proximal surfaces overlapping the second molar. The relationship between the third molar and the mandibular canal appeared closer in PAN and EBW than in CBCT.

Efficacy of digital radiographic systems in the quality assessment of intracanal materials used for primary teeth

Aim: To evaluate the performance of three digital radiographic systems in the analysis of root canal filling quality using different intracanal materials for primary teeth. Methods: Twenty-five bovine teeth were divided into 5 groups: Calen® combined with iodoform; Calen® combined with zinc oxide; zinc oxide and eugenol; UltraCal®XS, and 2% chlorhexidine combined with Ca(OH)2 + zinc oxide. Periapical radiographs were obtained with the VistaScan, Express, and SnapShot systems. The quality of the images was evaluated objectively (radiopacity) and subjectively (apical sealing and filling homogeneity). As the reference standard, the teeth were scanned with a micro-CT device. Results: Radiopacity differed among the radiographic systems and materials tested. In general, the greatest difference was observed between the Express and VistaScan systems; Calen® combined with iodoform resulted in the highest radiopacity. The radiographic systems did not differ in terms of homogeneity. However, Calen® combined with iodoform differed from the other materials and exhibited the best results. Regarding apical sealing, the SnapShot system and Calen® combined with zinc oxide provided the best results. Conclusion: Direct digital systems show better performance in evaluating the quality of endodontic treatment in primary teeth and should be preferred for this purpose

Dental age assessment: Which is the most applicable method?

To evaluate which method is the most applicable for estimating estimate dental age in Brazilian children, Nolla or Demirjian. For this purpose, both methods were reviewed and the differences between them brought to light. A total of 403 healthy children between the ages of 7 and 13 years with satisfactory panoramic radiographs, similar socio-economic background and ethnic origin were included. Panoramic radiographs were examined by the Nolla and Demirjian methods. Dental age was calculated for both methods, and the differences between the dental age and the chronological age were compared with analysis of variance with post hoc Dunnett. The Nolla method showed no significant difference in relation to chronological age in the majority of age groups for boys and girls, except for 12-year-old boys (over-estimation of 1.00) and between 11- and 12-year-old girls (over-estimation of 0.51 and 0.59, respectively). An over-estimation of the dental age was observed by using the Demirjian method (for boys 0.89-1.84 and for girls 0.69-1.97) for all age groups. The Nolla method is suitable for Brazilian children when it comes to age estimate with care to growth spurt beginning (around 11 and 12 years). However, the Dermijian method should not be used, because it over-estimated the age in both sexes.

Comparison of panoramic radiography and cone beam CT in the assessment of juxta-apical radiolucency.

OBJECTIVES: To compare the performance of panoramic radiography (PAN) and cone beam CT (CBCT) in the detection of juxta-apical radiolucency (JAR), as well as to investigate, in CBCT images, if there are factors associated with the detection of JAR on PAN. METHODS: Two oral radiologists assessed the presence of JAR in PAN and CBCT images of 175 individuals (308 mandibular third molars). The cortical plates involvement and the JAR size and location were assessed on CBCT to evaluate if these factors were related to JAR detection on PAN. McNemar's test and multiple logistic regression were performed. RESULTS: PAN and CBCT differed significantly in the detection of JAR (p = 0.001). On PAN, JAR was identified on 24% of the patients while on CBCT its detection increased to 32.6%. JAR was detected only on CBCT and only on PAN in 26 and 7 cases, respectively. Distal/mesial surfaces of dental roots were where JAR was mostly located (84.5%), cortical thinning was found in 59.2% of cases and the mean (SD) of JAR size was 5.03 (±1.8) mm. However, these factors were not associated with JAR detection on PAN (p > 0.05). On the other hand, the location of the cortical involvement (if buccal or lingual) was associated with JAR detection on PAN, which was more detectable when the thinning was on buccal cortical. CONCLUSIONS: Juxta-apical radiolucency is more often detected on CBCT than on PAN. JAR detection on PAN was improved when it was related to the buccal cortical plate of the mandible.

Concrescence: assessment of case by periapical radiography, cone beam computed tomography and micro-computed tomography.

The aim of this article was to describe imaging aspects of concrescence analyzed by three imaging modalities. A second molar joined together with a third molar was imaged using digital periapical radiography, cone beam computed tomography (CBCT) and micro-computed tomography (Micro-CT). On periapical radiograph, the mesial root of the third molar is superimposed on the distal root of the second molar. On CBCT images, a large cementum union between bulbous roots was detected, confirming the diagnosis of concrescence. On micro-CT images, the cementum union appeared limited to the apical third of the roots. In conclusion, both computed tomography modalities allowed for the diagnosis of concrescence. However, only micro-CT provided the real extension of the cementum union.