Uncertainty-based Active Learning by Bayesian U-Net for Multi-label Cone-beam CT Segmentation.

INTRODUCTION: Training of Artificial Intelligence (AI) for biomedical image analysis depends on large annotated datasets. This study assessed the efficacy of Active Learning (AL) strategies training AI models for accurate multilabel segmentation and detection of periapical lesions in cone-beam CTs (CBCTs) using a limited dataset. METHODS: Limited field-of-view CBCT volumes (n = 20) were segmented by clinicians (clinician segmentation [CS]) and Bayesian U-Net-based AL strategies. Two AL functions, Bayesian Active Learning by Disagreement [BALD] and Max_Entropy [ME], were used for multilabel segmentation ("Lesion"-"Tooth Structure"-"Bone"-"Restorative Materials"-"Background"), and compared to a non-AL benchmark Bayesian U-Net function. The training-to-testing set ratio was 4:1. Comparisons between the AL and Bayesian U-Net functions versus CS were made by evaluating the segmentation accuracy with the Dice indices and lesion detection accuracy. The Kruskal-Wallis test was used to assess statistically significant differences. RESULTS: The final training set contained 26 images. After 8 AL iterations, lesion detection sensitivity was 84.0% for BALD, 76.0% for ME, and 32.0% for Bayesian U-Net, which was significantly different (P < .0001; H = 16.989). The mean Dice index for all labels was 0.680 ± 0.155 for Bayesian U-Net and 0.703 ± 0.166 for ME after eight AL iterations, compared to 0.601 ± 0.267 for Bayesian U-Net over the mean of all iterations. The Dice index for "Lesion" was 0.504 for BALD and 0.501 for ME after 8 AL iterations, and at a maximum 0.288 for Bayesian U-Net. CONCLUSIONS: Both AL strategies based on uncertainty quantification from Bayesian U-Net BALD, and ME, provided improved segmentation and lesion detection accuracy for CBCTs. AL may contribute to reducing extensive labeling needs for training AI algorithms for biomedical image analysis in dentistry.

Developmental Correlates of Accelerated Molar Eruption in Early Childhood.

Background: Adversity has been linked to accelerated maturation. Molar eruption is a simple and scalable way to identify early maturation, but its developmental correlates remain unexplored. Thus, we examined whether accelerated maturation as indexed by molar eruption is associated with children's mental health or cognitive skills. Methods: Molar eruption was evaluated from T2-weighted magnetic resonance imaging in 117 children (63 female; ages 4-7 years). Parents reported on child mental health with the Child Behavior Checklist. Children completed standardized assessments of fluid reasoning, working memory, processing speed, crystallized knowledge, and math performance. Relationships between molar eruption and developmental outcomes were examined using linear models, with age, gender, and stress risk as covariates. Results: Earlier molar eruption was positively associated with children's externalizing symptoms (false discovery rate-corrected p [pFDR] = .027) but not internalizing symptoms, and the relationship with externalizing symptoms did not hold when controlling for stress risk. Earlier molar eruption was negatively associated with fluid reasoning (pFDR < .001), working memory (pFDR = .033), and crystallized knowledge (pFDR = .001). The association between molar eruption and both reasoning and crystallized knowledge held when controlling for stress risk. Molar eruption also partially mediated associations between stress risk and both reasoning (proportion mediated = 0.273, p = .004) and crystallized knowledge (proportion mediated = 0.126, p = .016). Conclusions: Accelerated maturation, as reflected in early molar eruption, may have consequences for cognitive development, perhaps because it constrains brain plasticity. Knowing the pace of a child's maturation may provide insight into the impact of a child's stress history on their cognitive development.

Correlation between TMJ Space Alteration and Disc Displacement: A Retrospective CBCT and MRI Study.

This study aims to determine if a large anterior and reduced posterior/superior joint space is highly predictable for disc displacement. From patients with temporomandibular disorders symptoms, fifty-two experimental joints and fourteen control joints were included. The cone beam computed tomography (CBCT) images were used to calculate posterior-to-anterior (P-A) and superior-to-anterior (S-A) joint space ratios, while disc position was determined using magnetic resonance imaging (MRI). One-way analysis of covariance test and receiver operating characteristics analysis were carried out. The results showed that among the 52 experimental joints, 45 were diagnosed as disc displacement and 7 as normal disc positions (N). All 14 control joints showed normal disc positions. The P-A ratio was 1.46 ± 0.21, 0.99 ± 0.23, and 0.86 ± 0.30 in the control, N, and DD groups, respectively (p < 0.001). The S-A ratio was 1.80 ± 0.27, 1.44 ± 0.33, and 1.08 ± 0.35 in the control, N, and DD groups, respectively (p < 0.001). When an altered P-A ratio and/or S-A ratio are observed on the CBCT, the diagnosis of disc displacement is quite predictable with high sensitivity and specificity.

Early life stress is associated with earlier emergence of permanent molars.

Exposure to adversity can accelerate biological aging. However, existing biomarkers of early aging are either costly and difficult to collect, like epigenetic signatures, or cannot be detected until late childhood, like pubertal onset. We evaluated the hypothesis that early adversity is associated with earlier molar eruption, an easily assessed measure that has been used to track the length of childhood across primates. In a preregistered analysis (n = 117, ages 4 to 7 y), we demonstrate that lower family income and exposure to adverse childhood experiences (ACEs) are significantly associated with earlier eruption of the first permanent molars, as rated in T2-weighted magnetic resonance images (MRI). We replicate relationships between income and molar eruption in a population-representative dataset (National Health and Nutrition Examination Survey; n = 1,973). These findings suggest that the impact of stress on the pace of biological development is evident in early childhood, and detectable in the timing of molar eruption.

Guidelines for oral and maxillofacial imaging: COVID-19 considerations.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus causing the current coronavirus disease 2019 (COVID-19) pandemic, is not only highly infectious but can induce serious outcomes in vulnerable individuals including dental patients and dental health care personnel (DHCPs). Responses to COVID-19 have been published by the Centers for Disease Control and Prevention and the American Dental Association, but a more specific response is required for the safe practice of oral and maxillofacial radiology. We aim to review the current knowledge of how the disease threatens patients and DHCPs and how to determine which patients are likely to be SARS-CoV-2 infected; consider how the use of personal protective equipment and infection control measures based on current best practices and science can reduce the risk of disease transmission during radiologic procedures; and examine how intraoral radiography, with its potentially greater risk of spreading the disease, might be replaced by extraoral radiographic techniques for certain diagnostic tasks. This is complemented by a flowchart that can be displayed in all dental offices.

Temporomandibular joint osteoarthritis: diagnosis and long-term conservative management: a topic review.

Degenerative joint disease (DJD), a common osteoarthritic problem encountered in clinical practice presents as a chronic debilitating disease resulting in altered joint structure due to degradation and loss of articular cartilage, along with changes in the subchondral bone and other soft tissues. DJD is a frequent finding in the Temporomandibular joints (TMJs). Consequently, a good understanding of the use of a diagnostic algorithm will lead to a better control of DJD in the TMJ. The etiopathogenesis of osteoarthritis is complex, and it is associated with multiple risk factors. The condition progresses slowly through different phases with periods of remission and activity finally reaching the burnout phase. Conservative management forms the cornerstone for the treatment of most of these cases. This review attempts to acquaint the dentist with the diagnosis, pathogenesis and general characteristics of the disease while highlighting and updating them with the current conservative treatment algorithms in order to assist in the formulation of a treatment plan for these patients.

Temporomandibular disorder in a patient with pseudoxanthoma elasticum: a case report and review.

Pseudoxanthoma elasticum (PXE) is a disorder characterized by progressive degeneration of elastic fibers and ectopic mineralization. Cutaneous manifestations are a hallmark of this disease and organs that may be affected by the disease process include cardiovascular, central nervous system, ocular and gastrointestinal systems. Oral manifestations of PXE have been previously reported as intramucosal nodules observed on various intraoral surfaces. We present a case of a 46-year-old female with PXE diagnosed with temporomandibular disorder (TMD). To our knowledge, this is the first report of a patient with TMD coexisting with PXE in the scientific literature.

Large, expansile odontogenic cyst with bilateral maxillary sinus involvement.

Residual cysts are common odontogenic lesions of the tooth-bearing areas of the jaws. A case of an unusually large residual cyst that crosses the maxillary midline and occupies portions of the maxillary sinuses is being reported. Investigations included a panoramic radiograph, CT scan and a biopsy. The differential diagnoses were common odontogenic lesions, including cysts and benign tumors. The value of advanced imaging modalities is stressed when determining the presence and extent of lesions in complex structures such as the maxilla. The need to visualize the entire lesion beyond what may be seen on intraoral views, as well as panoramic radiographs, is discussed.

Review of the complications associated with treatment of oropharyngeal cancer: a guide for the dental practitioner.

OBJECTIVES: Oropharyngeal cancer (OPC) is the sixth most common cancer worldwide. Focus on risk factors, improved diagnostic methods and effective management strategies have made it possible to successfully treat OPC. However, the 5-year survival rate has not improved for several years due to multiple treatment complications, tissue morbidity, loss of function, and diminished quality of life. Survivors are faced with complications like oral mucositis, hyposalivation, osteoradionecrosis, tissue fibrosis, morbidity from jaw resection, disfigurement, and loss of function that further diminish quality of life. The aim of this review is to highlight major complications associated with treatment of OPC via a literature search and review of available options for identification and management of these complications. DATA SOURCES: Relevant publications on oral complications of OPC therapy were thoroughly reviewed from the literature published between the years 1988 and 2012. We evaluated reported incidence, prevalence, and risk factors for oral complications of chemotherapy and radiotherapy for OPC. The authors conducted an electronic search using English language databases, namely PubMed Plus, Medline (Pre-Medline and Medline), Cochrane Database of Systematic Reviews (evidence-based medicine), Dentistry & Oral Sciences Source, A ccessScience, Embase, Evidence-Based Medicine Reviews Multifile, Google Scholar, ISI Journal Citation Reports, and Ovid Multi-Database. CONCLUSION: We identified the most common complications associated with the treatment of oral cancers. Based on the information gathered, there is evidence that survival of OPC extends beyond eradication of the diseased tissue. Understanding the potential treatment complications and utilizing available resources to prevent and minimize them are important. Caring for OPC survivors should be a multidisciplinary team approach involving the dentist, oncologist, internist, and social worker to improve the currently stagnant 5-year survival rate of OPC. More emphasis on improved quality of life after elimination of the cancer will ultimately improve OPC survivorship.

Large, expansile odontogenic cyst with bilateral maxillary sinus involvement.

Residual cysts are common odontogenic lesions of the tooth-bearing areas of the jaws. A case of an unusually large residual cyst that crosses the maxillary midline and occupies portions of the maxillary sinuses is being reported. Investigations included a panoramic radiograph, CT scan and a biopsy. The differential diagnoses were common odontogenic lesions, including cysts and benign tumors. The value of advanced imaging modalities is stressed when determining the presence and extent of lesions in complex structures such as the maxilla. The need to visualize the entire lesion beyond what may be seen on intraoral views, as well as panoramic radiographs, is discussed.

Keratocystic odontogenic tumor: systematic review with analysis of 72 additional cases from Mumbai, India.

OBJECTIVE: The aim of this systematic review was to assess the clinical and imaging findings of keratocystic odontogenic tumor (KOT). This article also attempts to determine the prevalence of KOTs and orthokeratinized odontogenic cyst (OOC) in the western Indian population and to compare demographic and radiographic findings of KOT of our cohort with that of the rest of the world. STUDY DESIGN: Relevant publications on KOT were reviewed from the published literature from 1976 to March 2012. Data regarding the 72 additional cases from Mumbai also were analyzed. RESULTS: Sixty-five reports were identified for this systematic review. The findings were divided into 4 global groups for analysis. The prevalence of KOT was 0.0173% and that of OOC 0.0012%. Male sex, mandible, and the unilocular variation were predominant for the additional cases. CONCLUSIONS: The characterization of the KOT lesions was accomplished, taking into consideration the variations to the western Indian population.

Familial white sponge nevus of the oral mucosa: report of occurrence in three generations.

White sponge nevus is a rare, inherited disorder that usually presents as nonpainful white plaque primarily involving the buccal mucosa, gingiva, and palate. Extraoral lesions most often occur in the esophagus or anogenital area, but almost invariably follow the development of typical buccal lesions. This article presents a familial case of white sponge nevus in which oral lesions were found in patients in three generations of the same family. Histologic findings include hyperkeratosis, acanthosis, and perinuclear eosinophilic condensation of epithelial cell cytoplasm, which serve to confirm white sponge nevus as the diagnosis. Clinical presentation and histopathology of white sponge nevus are discussed in relation to the differential diagnosis of other oral leukokeratoses.