Motion energy analysis during speech tasks in medication-naïve individuals with at-risk mental states for psychosis.

Movement abnormalities are commonly observed in schizophrenia and at-risk mental states (ARMS) for psychosis. They are usually detected with clinical interviews, such that automated analysis would enhance assessment. Our aim was to use motion energy analysis (MEA) to assess movement during free-speech videos in ARMS and control individuals, and to investigate associations between movement metrics and negative and positive symptoms. Thirty-two medication-naïve ARMS and forty-six healthy control individuals were filmed during speech tasks. Footages were analyzed using MEA software, which assesses movement by differences in pixels frame-by-frame. Two regions of interest were defined-head and torso-and mean amplitude, frequency, and coefficient of variability of movements for them were obtained. These metrics were correlated with the Structured Interview for Prodromal Syndromes (SIPS) symptoms, and with the risk of conversion to psychosis-inferred with the SIPS risk calculator. ARMS individuals had significantly lower mean amplitude of head movement and higher coefficients of movement variability for both head and torso, compared to controls. Higher coefficient of variability was related to higher risk of conversion. Negative correlations were seen between frequency of movement and most SIPS negative symptoms. All positive symptoms were correlated with at least one movement variable. Movement abnormalities could be automatically detected in medication-naïve ARMS subjects by means of a motion energy analysis software. Significant associations of movement metrics with symptoms were found, supporting the importance of movement analysis in ARMS. This could be a potentially important tool for early diagnosis, intervention, and outcome prediction.

Dosimetric evaluation for temporomandibular joint cone beam computed tomography exams using different field of view.

Objectives.To optimize the absorbed organ dose in relation to the field of view for temporomandibular joint examinations in four cone beam computed tomography devices.Methods.An anthropomorphic adult head and neck phantom, and 192 LiF dosimeters (TLD-100) were used. The dosimeters were placed in the region corresponding to the lens, parotid glands, submandibular glands, and thyroid. Small, medium and large FOVs were selected on Orthopantomograph OP300 Maxio, PaX-i3D Smart, ORTHOPHOS XG, and i-CAT Next Generation device when it was possible.Results.A wide range of absorbed dose values was recorded for all organs due to the different exposure parameters of each device. The radiosensitive organ with the highest dose was the parotid glands. The devices with 5 × 5 cm FOV recorded a lower dose in this protocol, while for the device without a small FOV (≤5 × 5 cm), the lowest dose was observed with the large FOV (6 × 16 cm).Conclusions.We recommend a double exposure with an FOV of 5 × 5 cm in the OP300 Maxio, PaX-i3D Smart, and ORTHOPHOS XG device, while in the i-CAT Next Generation device, a single exposure FOV of 6 × 16 cm is indicated.

Does the administration of meloxicam before head and neck radiotherapy reduce the risk of mandibular osteoradionecrosis? An animal model study.

OBJECTIVE: To assess whether the administration of meloxicam before head and neck radiotherapy reduces the risk of mandibular osteoradionecrosis in rats. MATERIAL AND METHODS: Sixty male Wistar rats were randomly divided into 6 groups (n = 10) according to the meloxicam administration and radiation therapy: control (C), irradiated (I), single dose of meloxicam (M1), single dose of meloxicam and irradiated (M1I), triple dose of meloxicam (M3), triple dose of meloxicam and irradiated (M3I). Meloxicam was administrated (20 mg/kg per dose) 1 h before the radiation therapy (single dose of 20 Gy) and 24 h and 48 h after the radiation therapy for groups with two additional doses. Ten days after the radiation therapy, the three right mandibular molars were extracted from all rats, who were euthanatized after 21 or 35 days (n = 5 per group). The mandibles were assessed by macroscopic evaluation and micro-CT analysis. RESULTS: The right hemimandibles of the irradiated groups revealed macroscopic signs of osteoradionecrosis, and those of the non-irradiated groups revealed complete gingival healing. A significant delay in alveolar socket healing in all irradiated groups was observed in the micro-CT assessment regardless meloxicam treatment. CONCLUSION: The administration of meloxicam before head and neck radiotherapy does not reduce the risk of mandibular osteoradionecrosis when associated to dental extractions. CLINICAL RELEVANCE: Since meloxicam has been shown to be a potential radiation-protective agent, and osteoradionecrosis physiopathology is believed to be related to an inflammatory process, possible interactions are relevant to be investigated.

Development and validation of two new image receptor-holding devices for overlapping reduction of proximal surfaces in bitewing radiography: a preclinical study.

OBJECTIVE: To create and validate two new Image Receptor-Holding devices (IRHDs) to reduce proximal surfaces overlapping in bitewing radiography in comparison to a regular well-established and commercially available IRHD. METHODS: Two IRHDs for bitewing radiographs with a wedge on the biting surface were designed and 3D-printed. These IRHDs, with a large wedge (Pr-Lw) and small wedge (Pr-Sw), were compared with a regular commercially available IRHD (Rinn XCP®) during image acquisition of bitewing radiographs of four posterior regions (one upper region and three lower regions) in two dry skulls and mandibles. A total of 156 interproximal regions on bitewing radiographs were radiographed by 13 oral radiology graduate students and independently assessed by two oral radiologists (10 years of experience). IRHDs were compared by Cochran's Q test regarding the number of overlapped proximal surfaces in the acquired radiographs with a significance level of 5%. RESULTS: The observers were in perfect agreement (κ = 1.0) to classify the proximal surfaces overlapping. The Pr-Lw IRHD presented the lowest number of surfaces overlapping (19.2%) followed by the Pr-Sw IRHD (48.1%) and the XCP®IRHD with the highest surfaces overlapping (71.2%). The Pr-Lw IRHD surfaces overlapping was statistically different from the XCP IRHD (p < 0.001), and the Pr-Sw IRHD (p = 0.014). CONCLUSIONS: The Pr-Lw IRHD demonstrated the most efficient performance in overlapping surfaces reduction, compared with the Pr-Sw IRHD and the XCP® IRHD in adult dry skulls and mandibles.

Efficacy and Safety of Botulinum Toxin Type A on Persistent Myofascial Pain: A Randomized Clinical Trial.

This study assessed the safety and efficacy of three different doses of BoNT-A for persistent myofascial pain (MFP). One hundred female subjects were randomly assigned into five groups (n = 20): oral appliance (OA), saline solution (SS) and three BoNT-A groups with different doses. Pain intensity and pressure pain threshold were evaluated up to 24 weeks after treatment. Adverse effects related to muscle contraction, masticatory performance, muscle thickness and mandibular bone volume were also assessed. Changes over time were compared within and between groups. The "nparLD" package and Wilcoxon signed-rank test were used to analyze the data. BoNT-A reduced pain intensity (p < 0.0001) and increased pressure pain threshold (p < 0.0001) for up to 24 weeks compared to the placebo. No differences were found between BoNT-A and OA at the last follow-up. A transient decline in masticatory performance (p < 0.05) and muscle contraction (p < 0.0001), and a decrease in muscle thickness (p < 0.05) and coronoid and condylar process bone volume (p < 0.05) were found as dose-related adverse effects of BoNT-A. Regardless of the dose, BoNT-A was as effective as OA on MFP. Notwithstanding, due to BoNT-A dose-related adverse effects, we suggest the use of low doses of BoNT-A in MFP patients that do not benefit from conservative treatments.

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.

A modified protocol of mandibular osteoradionecrosis induction in rats with external beam radiation therapy.

OBJECTIVE: To propose a modified protocol of mandibular osteoradionecrosis induction in rats with external beam radiation therapy. MATERIAL AND METHODS: A total of 45 male Wistar rats were used in this study. Firstly, 25 rats were divided into 5 groups (n = 5) according to the radiation dose protocol: without irradiation and irradiated with 15 Gy, 20 Gy, 25 Gy, or 30 Gy using a linear accelerator. Secondly, 15 other rats were divided into 3 groups (n = 5) according to the time of extraction of the three right mandibular molars: 7, 10, or 14 days after irradiation of 20 Gy. Lastly, dental extractions were performed in 5 other rats without irradiation (C-E10) for comparison with those of the group of dental extractions 10 days after irradiation (I-E10). RESULTS: The irradiated animals survived throughout the study period only at single doses of 15 Gy and 20 Gy. The suitable time for dental extractions after irradiation to induce mandibular osteoradionecrosis was defined as 10 days. Macroscopic evaluation of the right hemimandibles showed presence of osteoradionecrosis in I-E10 group and complete gingival healing in C-E10 group. CONCLUSION: A single radiation dose of 20 Gy focused on head and neck region combined with the extraction of the three mandibular molars 10 days after irradiation constitutes a feasible protocol of mandibular osteoradionecrosis induction in rats with external beam radiation therapy. CLINICAL RELEVANCE: Establishing a solid and widely available protocol of mandibular osteoradionecrosis induction is essential in the search for methods to prevent this complex disease.

Feasibility of micro-computed tomography to detect and classify proximal caries lesions in vitro.

BACKGROUND: Micro-computed tomography (micro-CT) has been widely described as a nondestructive in vitro imaging method although its accuracy for caries detection is still unclear. The aim of this study was to investigate the feasibility of micro-CT to detect and classify proximal caries lesions in posterior teeth, using different protocols. MATERIALS AND METHODS: In this in vitro study, crowns of 122 human teeth were scanned with Skyscan 1174 (Bruker, Kontich, Belgium) using the full-scan mode (360°). Reconstruction of 900 basis images was performed using NRecon Software (Bruker, Kontich, Belgium) for the protocol 1 (full-scan mode 360°), and 450 basis images were used to reconstruct the protocol 2 (half-scan mode 180°). Three observers analyzed the reconstructed images concerning the presence and depth of proximal caries lesions (244 surfaces). To determine the presence/absence and depth of caries lesions, histological examination was conducted as reference standard level of significance McNemar and McNemar-Bowker tests compared the methods studied and the gold standard (P < 0.05). RESULTS: The intra- and inter-observer agreement for both methods ranged from moderate to excellent. There was no difference between both micro-CT methods and histology for the presence of lesions (P > 0.05). However, both methods differed with the reference standard for depth (P < 0.05). The disagreement occurred mostly in cases of enamel lesions. The highest diagnostic values were found for 180° rotation. Micro-CT performed well in detecting caries lesions compared to histology, meanwhile the classification of their depth presented lower values. Scan mode did not influence the detection. CONCLUSION: Both protocols of micro-CT tested presented an overall satisfactory performance in detecting proximal caries lesions; however, for the depth classification, the method was not accurate.

Diagnostic Accuracy of Periapical Radiography and Cone-beam Computed Tomography in Identifying Root Canal Configuration of Human Premolars.

INTRODUCTION: The aim of this study was to assess the diagnostic accuracy of periapical radiography (PR) and cone-beam computed tomographic (CBCT) imaging in the detection of the root canal configuration (RCC) of human premolars. METHODS: PR and CBCT imaging of 114 extracted human premolars were evaluated by 2 oral radiologists. RCC was recorded according to Vertucci's classification. Micro-computed tomographic imaging served as the gold standard to determine RCC. Accuracy, sensitivity, specificity, and predictive values were calculated. The Friedman test compared both PR and CBCT imaging with the gold standard. RESULTS: CBCT imaging showed higher values for all diagnostic tests compared with PR. Accuracy was 0.55 and 0.89 for PR and CBCT imaging, respectively. There was no difference between CBCT imaging and the gold standard, whereas PR differed from both CBCT and micro-computed tomographic imaging (P < .0001). CBCT imaging was more accurate than PR for evaluating different types of RCC individually. Canal configuration types III, VII, and "other" were poorly identified on CBCT imaging with a detection accuracy of 50%, 0%, and 43%, respectively. With PR, all canal configurations except type I were poorly visible. CONCLUSIONS: PR presented low performance in the detection of RCC in premolars, whereas CBCT imaging showed no difference compared with the gold standard. Canals with complex configurations were less identifiable using both imaging methods, especially PR.