Optimizing cone-beam computed tomography exposure for an effective radiation dose and image quality balance.

Purpose: The aim of this study was to evaluate the influence of different cone-beam computed tomography (CBCT) acquisition protocols on reducing the effective radiation dose while maintaining image quality. Materials and Methods: The effective dose emitted by a CBCT device was calculated using thermoluminescent dosimeters placed in a Rando Alderson phantom. Image quality was assessed by 3 experienced evaluators. The relationship between image quality and confidence was evaluated using the Fisher exact test, and the agreement among raters was assessed using the kappa test. Multiple linear regression analysis was performed to investigate whether the technical parameters could predict the effective dose. P-values<0.05 were considered to indicate statistical significance. Results: The optimized protocol (3 mA, 99 kVp, and 450 projection images) demonstrated good image quality and a lower effective dose for radiation-sensitive organs. Image quality and confidence had consistent values for all structures (P<0.05). Multiple linear regression analysis resulted in a statistically significant model. The milliamperage (b=0.504; t=3.406; P=0.027), kilovoltage peak (b=0.589; t=3.979; P=0.016) and number of projection images (b=0.557; t=3.762; P=0.020) were predictors of the effective dose. Conclusion: Optimized CBCT acquisition protocols can significantly reduce the effective radiation dose while maintaining acceptable image quality by adjusting the milliamperage and projection images.

Diagnostic capability of artificial intelligence tools for detecting and classifying odontogenic cysts and tumors: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the diagnostic capability of artificial intelligence (AI) for detecting and classifying odontogenic cysts and tumors, with special emphasis on odontogenic keratocyst (OKC) and ameloblastoma. STUDY DESIGN: Nine electronic databases and the gray literature were examined. Human-based studies using AI algorithms to detect or classify odontogenic cysts and tumors by using panoramic radiographs or CBCT were included. Diagnostic tests were evaluated, and a meta-analysis was performed for classifying OKCs and ameloblastomas. Heterogeneity, risk of bias, and certainty of evidence were evaluated. RESULTS: Twelve studies concluded that AI is a promising tool for the detection and/or classification of lesions, producing high diagnostic test values. Three articles assessed the sensitivity of convolutional neural networks in classifying similar lesions using panoramic radiographs, specifically OKC and ameloblastoma. The accuracy was 0.893 (95% CI 0.832-0.954). AI applied to cone beam computed tomography produced superior accuracy based on only 4 studies. The results revealed heterogeneity in the models used, variations in imaging examinations, and discrepancies in the presentation of metrics. CONCLUSION: AI tools exhibited a relatively high level of accuracy in detecting and classifying OKC and ameloblastoma. Panoramic radiography appears to be an accurate method for AI-based classification of these lesions, albeit with a low level of certainty. The accuracy of CBCT model data appears to be high and promising, although with limited available data.

Traumatic Ulcerative Granuloma with Stromal Eosinophilia on the Tongue.

BACKGROUND: Traumatic Ulcerative Granuloma with Stromal Eosinophilia, commonly known as Eosinophilic Ulcer, is a reactive solitary and self-limiting benign lesion. It manifests as a punched-out ulcer with a distinct surrounding indurated border, often raising concerns about malignancy. METHODS: A 44-year-old male presented with a painless, indurated tongue ulcer evolving over three months. Despite being asymptomatic, the patient underwent an incisional biopsy due to suspicions of oral squamous cell carcinoma. RESULTS: Histological analysis revealed a disrupted epithelial lining, dense necrotic connective tissue, and a fibrino-purulent pseudomembrane. Proximal to the ulcer, a collar-like projection of reactive epithelial tissue hyperplasia was noted, accompanied by mononuclear cells and a predominantly histiocytic infiltrate in the submucosal layer surrounding skeletal muscle fibers. The final diagnosis was Traumatic Ulcerative Granuloma with Stromal Eosinophilia. Remarkably, the lesion spontaneously healed within 2 weeks post-biopsy, with no recurrence over 6 months. CONCLUSION: This case emphasizes considering this benign condition in the differential diagnosis of oral ulcers, highlighting the importance of accurate histopathological evaluation to rule out cancer.

Accuracy of cone-beam computed tomography in determining gingival thickness: a systematic review and meta-analysis.

OBJECTIVE: To assess the accuracy of cone-beam computed tomography (CBCT) for determining gingival thickness. MATERIAL AND METHODS: Searches were undertaken in PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, LIVIVO, and gray literature (Google Scholar and ProQuest) for studies considered eligible according to the following criteria: cross-sectional observational studies, which compared CBCT accuracy with that of transgingival probing when determining gingival thickness, in adult patients with good periodontal health. No language or time restrictions were applied in this systematic review. The risk of bias was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for analytical cross-sectional studies. RESULTS: Six articles were included for qualitative synthesis, involving a pooled sample of 132 patients with a mean age of 29 years (18-51 years). Of these 6 studies, 5 were eligible for quantitative analysis. The meta-analysis showed no statistically significant difference between CBCT and transgingival probing measures of gingival tissue (mean difference of 0.10 (95% CI-0.17-0.38). No significant level of heterogeneity was detected (Tau2-P = 0.0662; I2 = 0%; H2-P = 1.000; Q-P = 1.134). According to the GRADE criterion, confidence in the cumulative evidence was considered low. CONCLUSIONS: CBCT is an accurate method for determining gingival tissue thickness, comparable to the reference standard (transgingival probing). CLINICAL RELEVANCE: CBCT could be considered for gingival thickness measurement when bone thickness is also needed, and thereby aid in the assessment of gingival biotype without the discomfort and anesthesia needed in transgingival probing. TRIAL REGISTRATION: This protocol was registered at the PROSPERO database (International Prospective Register of Systematic Review) under registration number CRD42022326970. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022326970 .

Influence of the technical parameters of CBCT image acquisition on vertical root fracture diagnosis: a systematic review and meta-analysis.

OBJECTIVES: To evaluate the influence of image acquisition parameters (voxel, FOV, kVp, mA) on the accuracy of cone-beam computed tomography (CBCT) in detecting vertical root fracture (VRF). MATERIAL AND METHODS: Searches were performed in 6 main databases and the gray literature, without restrictions of language or date. Observational clinical studies (OCS) and in vitro-extracted teeth (IV) studies were considered eligible for inclusion when investigating the accuracy (sensitivity, specificity) of CBCT in detecting VRF in human teeth. The risk of bias was assessed using QUADAS-2, and a meta-analysis was performed using Review Manager v5.4 software and Jamovi software v1.6. RESULTS: A total of 60 out of 132 articles was included after fulfilling the eligibility criteria. Of these, 54 were IV studies while 6 were OCS. In the IV studies, it was seen that smaller FOV sizes tended to present higher accuracy values. The meta-analysis of the 6 OCS showed that the overall sensitivity and specificity values for 0.08 mm and 0.1 mm voxels were greater (0.84 and 0.79, respectively) than the sensitivity and specificity values for 0.125 mm and 0.2 mm voxels (0.70 and 0.55, respectively). CONCLUSIONS: Despite the uncertain risk of bias found for the IV and OCS studies, smaller voxel and FOV sizes seem to provide more accurate VRF detection values when using CBCT. CLINICAL RELEVANCE: This information is crucial for supporting the clinician when prescribing CBCT in cases of a clinical suspicion of VRF, and contributes to the personalization of the CBCT prescription, thereby ensuring greater accuracy in the VRF diagnosis. Registration This protocol was registered at the PROSPERO database (International Prospective Register of Systematic Review) under registration number CRD42020210118.

Accuracy of artificial intelligence for tooth extraction decision-making in orthodontics: a systematic review and meta-analysis.

OBJECTIVE: This study aimed to analyze the accuracy of artificial intelligence (AI) for orthodontic tooth extraction decision-making. MATERIALS AND METHODS: PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, LIVIVO, Computers & Applied Science, ACM Digital Library, Compendex, and gray literature (OpenGrey, ProQuest, and Google Scholar) were electronically searched. Three independent reviewers selected the studies and extracted and analyzed the data. Risk of bias, methodological quality, and certainty of evidence were assessed by QUADAS-2, checklist for AI research, and GRADE, respectively. RESULTS: The search identified 1810 studies. After 2 phases of selection, six studies were included, showing an unclear risk of bias of patient selection. Two studies showed a high risk of bias in the index test, while two others presented an unclear risk of bias in the diagnostic test. Data were pooled in a random model and yielded an accuracy value of 0.87 (95% CI = 0.75-0.96) for all studies, 0.89 (95% CI = 0.70-1.00) for multilayer perceptron, and 0.88 (95% CI = 0.73-0.98) for back propagation models. Sensitivity, specificity, and area under the curve of the multilayer perceptron model yielded 0.84 (95% CI = 0.58-1.00), 0.89 (95% CI = 0.74-0.98), and 0.92 (95% CI = 0.72-1.00) scores, respectively. Sagittal discrepancy, upper crowding, and protrusion showed the highest ranks weighted in the models. CONCLUSIONS: Orthodontic tooth extraction decision-making using AI presented promising accuracy but should be considered with caution due to the very low certainty of evidence. CLINICAL RELEVANCE: AI models for tooth extraction decision in orthodontics cannot yet be considered a substitute for a final human decision.

Binary and WHO dysplasia grading systems for the prediction of malignant transformation of oral leukoplakia and erythroplakia: a systematic review and meta-analysis.

OBJECTIVES: The aim of this systematic review was to examine the evidence of the binary histologic grading system capacity for predicting malignant transformation and to compare it with that of the WHO systems. MATERIAL AND METHODS: A systematic review was conducted, using PubMed, EMBASE, LILACS, Web of Science, Scopus, and LIVIVO databases without any language or timeframe restrictions. Studies were included if they compared the binary and the WHO histologic grading systems in the prediction of malignant transformation of oral epithelial dysplasia (OED). RESULTS: The capacity of the WHO and binary grading systems to predict malignant transformation ranged from 16 to 80% and from 5 to 80%, respectively. The pooled malignant transformation rate of lesions classified as severe dysplasia or carcinoma in situ by the WHO grading was 40% (95% confidence interval (CI), 0.02-0.87; I2 = 92%; P = 0.00), while the corresponding value for lesions classified as high-risk by the binary grading system was 31% (95% CI, 0.00-0.84; I2 = 97%; P = 0.00). Overall, there was no significant difference in prognostication accuracy between the WHO and the binary systems (odds ratio = 2.02; 95% CI, 0.88-4.64). CONCLUSIONS: Although some studies suggest that the binary system is associated with lower inter-rater variability when grading OED, the evidence remains inconclusive on whether this system is superior to that of the WHO at predicting malignant transformation. CLINICAL RELEVANCE: The reproducibility of the binary system has the potential to be better for prognostic purposes. However, there is no high-quality evidence to confirm if this advantage may assist clinicians in decision-making.

Dentin thickness as a risk factor for vertical root fracture in endodontically treated teeth: a case-control study.

OBJECTIVES: This study evaluated factors associated with vertical root fracture in endodontically treated teeth, using a cone-beam computed tomography (CBCT) image database. MATERIALS AND METHODS: The sample for this case-control study consisted of 81 CBCT scans of teeth with vertical root fracture (VRF) and 81 CBCT scans of non-fractured teeth, matched by age, sex, and tooth position. The analyzed variables included dentin thickness, an intraradicular post, an adjacent implant, and a missing adjacent tooth. Student's t test test was used to compare the quantitative variables. The chi-square test was used to compare the categorical variables. Logistic regression was performed to evaluate the association between the presence of VRF and the independent factors assessed. RESULTS: The mean dentin thickness of fractured teeth was 1.3 mm, whereas that of non-fractured ones was 1.5 mm (p < 0.001). There was no difference between the fractured and non-fractured groups, regarding implant frequency or missing adjacent tooth (p > 0.05). There were a significantly larger number of teeth with posts in the fractured versus non-fractured group (p = 0.007). However, dentin thickness ≤ 1.3 mm was the only factor associated with VRF in the multiple regression model (OR = 3.60, 95%CI = 1.76-7.37). CONCLUSIONS: Dentin thickness may influence the development of VRF. Dentin thickness ≤ 1.3 mm is associated with a greater likelihood of fracture than ≥ 1.4 mm. CLINICAL RELEVANCE: This study suggests there may be a minimum amount of safe dentin thickness that should be preserved after endodontic instrumentation.

Influence of voxel size on cone-beam computed tomography-based detection of vertical root fractures in the presence of intracanal metallic posts.

PURPOSE: This study was performed to evaluate the influence of voxel size and the accuracy of 2 cone-beam computed tomography (CBCT) systems in the detection of vertical root fracture (VRF) in the presence of intracanal metallic posts. MATERIALS AND METHODS: Thirty uniradicular extracted human teeth were selected and randomly divided into 2 groups (VRF group, n=15; and control group, n=15). The VRFs were induced by an Instron machine, and metallic posts were placed in both groups. The scans were acquired by CBCT with 4 different voxel sizes: 0.1 mm and 0.16 mm (for the Eagle 3D V-Beam system) and 0.125 mm and 0.2 mm (for the i-CAT system) (protocols 1, 2, 3, and 4, respectively). Interobserver and intraobserver agreement was assessed using the Cohen kappa test. Sensitivity and specificity were evaluated and receiver operating characteristic analysis was performed. RESULTS: The intraobserver coefficients indicated good (0.71) to very good (0.83) agreement, and the interobserver coefficients indicated moderate (0.57) to very good (0.80) agreement. In respect to the relationship between sensitivity and specificity, a statistically significant difference was found between protocols 1 (positive predictive value: 0.710, negative predictive value: 0.724) and 3 (positive predictive value: 0.727, negative predictive value: 0.632) (P<.05). The least interference due to artifact formation was observed using protocol 2. CONCLUSION: Protocols with a smaller voxel size and field of view seemed to favor the detection of VRF in teeth with intracanal metallic posts.

Effect of Alendronate on Bone Microarchitecture in Irradiated Rats With Osteoporosis: Micro-CT and Histomorphometric Analysis.

PURPOSE: The aim of the present study was to evaluate the effect of alendronate (ALN) on the bone microarchitecture of irradiated rats with estrogen deficiency, using microcomputed tomography (micro-CT) and histomorphometric analysis. MATERIALS AND METHODS: Forty adult Wistar rats were subjected to ovariectomy and randomly divided into the following groups: control (CON), ALN, irradiated (IRR), and ALN/irradiated (ALN/IRR). Approximately 50 days after ovariectomy, the hind limbs of the rats in the IRR and ALN/IRR groups were irradiated with 15 Gy of x-radiation. The rats were euthanized 7 and 30 days after irradiation. The bone microarchitecture was analyzed using micro-CT and histomorphometry. The bone microarchitecture was evaluated using the Mann-Whitney U test, analysis of variance, and the post hoc Tukey test, with statistical significance set at 5%. RESULTS: Irradiation had increased the thickness of the cortical bone at 7 days (P < .05) and also decreased the number of trabeculae per unit length and increased the average distance between the trabeculae (P < .05) at 30 days. ALN inhibited the deleterious effect of x-radiation, preventing the distance between the trabeculae from increasing and the number of trabeculae per unit length from decreasing (P < .05). CONCLUSIONS: The present results have demonstrated that the initial effect of ALN could be positive, because it checked the deleterious action in the bone tissue submitted to x-radiation.

20-year Follow-up of Recurrent Glandular Odontogenic Cyst Mimicking a Periapical Lesion.

Periapical lesions usually are caused by root canal infection; nevertheless, other pathologies may eventually involve the tooth apex, making the correct diagnosis more difficult. Glandular odontogenic cysts (GOCs) are uncommon and, despite their cystic nature, may present an aggressive behavior and a high recurrence rate. This report describes a recurrent GOC mimicking a periapical lesion that was followed up for 20 years. A 45-year-old woman described tooth discomfort for several years in the anterior region of the mandible that was not exacerbated during eating or occlusion. Clinical examination revealed no signs of swelling, redness, or inflammation in the gingival or surrounding soft tissue. Nevertheless, periapical radiography showed a well-defined large radiolucent lesion in the periapical region of teeth #22, #23, #24, and #25. The pulp test confirmed that all these teeth were vital. An incisional biopsy was performed, and with the histopathological diagnosis of an odontogenic cyst, the lesion was enucleated surgically. After recurrence, the extensive periapical multilocular lesions were again surgically removed. Based on the microscopic findings, the final diagnosis was GOC. One year later, there were no signs of recurrence. GOCs associated with the root apex may mimic periapical inflammatory diseases. Clinical, radiographic, and histopathological findings are essential for the diagnosis of inconclusive radiolucent findings in the periapical region. Biopsy specimens should be sent to a specialized oral pathology laboratory.

E-cadherin downregulation and Twist overexpression since early stages of oral carcinogenesis.

There is some evidence of Twist participation in oral carcinogenesis; however, little is known about its interaction with E-cadherin in oral squamous cell carcinoma (OSCC) development. This experimental study included an immunohistochemical analysis of Twist and E-cadherin proteins in paraffin-embedded specimens of oral leukoplakia (OL), OSCC, and normal oral mucosa. In addition, it was also performed a Western blot and double-immunofluorescence analysis of Twist and E-cadherin expression in OSCC cell lines. Significant differences in Twist and E-cadherin immunoexpression were observed between normal oral mucosa and OL, with an inverse relation since the earliest stages of oral dysplasia (r = -0,512; P < 0.001). Western blot and double-immunofluorescence analysis showed differences in Twist and E-cadherin expression among human oral keratinocytes and OSCC cell lines suggesting that downregulation of E-cadherin occurs in a dependent manner of Twist in OSCC. Our results showed a possible value of Twist and E-cadherin in the prediction of risk of oral epithelium malignant transformation.

Nuclear factor κB and cyclooxygenase-2 immunoexpression in oral dysplasia and oral squamous cell carcinoma.

Oral leukoplakia is the main potentially malignant oral lesion, and oral squamous cell carcinoma accounts for more than 95% of all malignant neoplasms in the oral cavity. Therefore, the aim of this study was to verify the immunoexpression of nuclear factor κB (NF-κB) and cyclooxygenase-2 (COX-2) proteins in dysplastic oral lesions and oral squamous cell carcinoma. Immunohistochemical reactions were performed on 6 inflammatory fibrous hyperplasia, 28 oral leukoplakia, and 15 oral squamous cell carcinoma paraffin-embedded samples. Immunoperoxidase reaction for NF-κB and COX-2 was applied on the specimens, and the positivity of the reactions was calculated for 1000 epithelial cells. Using the analysis of variance and the Tukey post hoc statistical analyses, a significantly increased immunoexpression for NF-κB was observed when oral squamous cell carcinoma samples were compared with the other groups studied. However, using the Kruskal-Wallis and the Dunn post hoc tests, a statistically significant result for COX-2 expression was obtained only when the moderate dysplasia group was compared with the inflammatory fibrous hyperplasia group. Nuclear factor κB may participate in the malignant phenotype acquisition process of the oral squamous cell carcinoma in its late stages, whereas COX-2 may be involved in the early stages of oral carcinogenesis process.

Oral candidiasis mimicking an oral squamous cell carcinoma: report of a case.

Oral candidiasis is a significant problem in immune-compromised patients. The most common forms of mucosal candidiasis are oropharyngeal, oesophageal and vaginal, and more than 90% of HIV positive persons will manifest at least one episode of oropharyngeal candidiasis. Local and systemic factors such as uninterrupted daily use of a prosthesis by patients, smoking habit, as well as high glucose intake may contribute to the development of the lesion. The aim of this article is to report an uncommon case of oral candidiasis presenting an aggressive clinical behaviour in a 64-year-old male patient, with a significant smoking habit and a medical history of non-controlled diabetes. The lesion affected the hard and soft palate of the right side, revealing erythematous and ulcerated areas, elevated borders and central portions resembling necrosis, mimicking the clinical features of oral squamous cell carcinoma. However, the correct diagnosis of oral candidiasis was obtained after histopathological and cytological examinations and the patient was easily treated with traditional antifungal drugs and correction of his glucose levels.

Kaposi sarcoma and paracoccidioidomycosis in the same fragment of oral mucosa biopsy: a rare association in human immunodeficiency virus-positive patient. A case report.

The immunossuppression caused by HIV infection makes the affected individuals more susceptible to some diseases including infections, neoplasms, or even the association between them. Kaposi sarcoma (KS) is the most common AIDS-related neoplasm, featured as an angioproliferative disorder. Its cause seems to be related to the human herpesvirus type 8 and it is usually associated with lower CD4+ T cell count. Oral involvement is frequent, presenting red to blue-purplish plaques, maculaes, and nodules. On the other hand, paracoccidioidomycosis (PCM) is a systemic mycosis, endemic in Latin America, caused by Paracoccidioides brasiliensis. This mycosis is not commonly related to human immunodeficiency virus (HIV) infection, although PCM can be present in immunosuppression cases. Oral lesions, as granulomatous ulcers, are often identified in seropositive patients with PCM. A rare case, in which a male HIV-positive patient presented simultaneously Kaposi sarcoma and PCM in the same fragment of oral mucosa biopsy, is described. To the best of our knowledge, this concomitant association had not been previously described.