The "5Ts" screening tool: Enhancements and threshold values for effective TMD identification.

OBJECTIVE: This study aimed to enhance the quintessential "five temporomandibular disorder (TMD) symptoms" (5Ts) screener by incorporating frequency options and distinguishing between TMJ and muscle pain. The diagnostic accuracy along with cut-off points for the effective identification of TMDs was also established. METHODS: Participants, aged ≥18 years, were recruited from a university-based hospital. After completing surveys encompassing demographic data and the enhanced 5Ts (with frequency options [5Ts-F] and differentiation of TMJ/muscle pain [6Ts-F]), protocolized interviews and clinical examinations were performed following DC/TMD. The diagnostic accuracy and best cut-off points were determined with the area under the receiver operating characteristic curves (AUCs). RESULTS: 324 participants were recruited (mean age 30.0 ± 11.4 years). Among these, 86.4% had TMDs. 5Ts exhibited high diagnostic accuracy for detecting all TMDs (AUC = 0.92) with sensitivity/specificity values of 83.9%/88.6%. Both 5Ts-F and 6Ts-F had slightly better accuracy (AUCs = 0.95/0.96), comparable sensitivity, and superior specificity (97.7%) compared to 5Ts. The best cut-off points were 1.5 for 5Ts and 2.5 for 5Ts-F/6Ts-F. CONCLUSIONS: Although all three TMD screeners presented high diagnostic accuracy, 5Ts-F/6Ts-F had notably improved specificity. 5Ts scores of >1.5 and 5Ts-F/6Ts-F scores of >2.5 are to be applied for screening the presence of TMDs.

[Research status and outlook of deep learning in oral and maxillofacial medical imaging].

Artificial intelligence, represented by deep learning, has received increasing attention in the field of oral and maxillofacial medical imaging, which has been widely studied in image analysis and image quality improvement. This narrative review provides an insight into the following applications of deep learning in oral and maxillofacial imaging: detection, recognition and segmentation of teeth and other anatomical structures, detection and diagnosis of oral and maxillofacial diseases, and forensic personal identification. In addition, the limitations of the studies and the directions for future development are summarized.

[Research status and outlook of deep learning in oral and maxillofacial medical imaging].

Artificial intelligence, represented by deep learning, has received increasing attention in the field of oral and maxillofacial medical imaging, which has been widely studied in image analysis and image quality improvement. This narrative review provides an insight into the following applications of deep learning in oral and maxillofacial imaging: detection, recognition and segmentation of teeth and other anatomical structures, detection and diagnosis of oral and maxillofacial diseases, and forensic personal identification. In addition, the limitations of the studies and the directions for future development are summarized.

Ecdysis triggering hormone is essential for larva-pupa-adult transformation in Leptinotarsa decemlineata.

In Drosophila melanogaster, ecdysis triggering hormone (ETH) is the key factor triggering ecdysis behaviour and promoting trachea clearance. However, whether ETH plays the dual roles in non-dipteran insects is unknown. In this survey, we found that Ldeth mRNA levels were positively correlated with circulating 20-hydroxyecdysone (20E) titers in Leptinotarsa decemlineata. Ingestion of an ecdysteroid agonist halofenozide or 20E stimulated the transcription of Ldeth, whereas RNA interference (RNAi) of ecdysteroidogenesis (LdPTTH or LdSHD) or 20E signalling (LdEcR, LdUSP or LdFTZ-F1) genes inhibited the expression, indicating ETH acts downstream of 20E. RNAi of Ldeth at the final instar stage impaired pupation. More than 80% of the Ldeth-depleted beetles remained as prepupae, completely wrapped in the old larval cuticles. These prepupae became withered, dried and darkened gradually, and finally died in soil. The remaining Ldeth hypomorphs pupated and emerged as abnormal adults, bearing smaller and wrinkle elytrum and hindwing. Moreover, the tracheae in the Ldeth hypomorphs were full of liquid. We accordingly proposed that the failure of trachea clearance disenabled air-swallowing after pupa-adult ecdysis and impacted wing expansion. Our results suggest that ETH plays the dual roles, initiation of ecdysis and motivation of trachea clearance, in a coleopteran.

[Experts consensus on MRI examination specification and diagnostic criteria of temporomandibular joint disc displacement].

The document represented the consensus amongst the professionals from the Society of TMD & Occlusion, Chinese Stomatological Association and provided guidelines with the MRI examination specification and diagnostic criteria of temporomandibular joint disc displacement.

[Experts consensus on cone-beam CT examination specification and diagnostic criteria of temporomandibular disorders].

The document represented the consensus amongst the professionals from the Society of TMD & Occlusion, Chinese Stomatological Association and provided guidelines with the cone-beam CT examination specification and diagnostic criteria of temporomandibular disorders.

[Three-dimensional quantitative evaluation of condylar bone remodeling of temporomandibular joint based on cone-beam CT imaging].

Objective: To establish a three-dimensional （3D） quantitative measurement and evaluate the condylar bone remodeling of temporomandibular joint (TMJ). Methods: Pre-and post-treatment cone-beam CT (CBCT) data were obtained from 41 patients ï¼»10 males, 31 females, mean age of (19.7±4.4) years (12-30 years old)ï¼½, who visited the Center for TMD and Orofacial Pain, Peking University School and Hospital of Stomatology from November 2014 to August 2019, and diagnosed with acute disc displacement without reduction or disc displacement with reduction, with intermittent locking and treated by manual disc reduction followed by anterior repositioning splint. First, condylar bone remodeling was evaluated according to the number of "double contour image" and qualitatively classified as no remodeling (no double contour image), partial remodeling (1-4 double contour images) and remarkable remodeling (5-6 double contour images). Then, condylar bone remodeling was quantitatively evaluated by CBCT based 3D measurement: segmenting condylar images using a semi-automatic method of the manually preliminary mark combined with watershed algorithm, reconstructing the surface models, superimposing the pre-and post-treatment condylar images and finally calculating the volumetric differences of condyle and condylar head, respectively. Results: The Kappa values of two-dimensional (2D) qualitative evaluation were 0.66-0.87, and 3D quantitative measurements of condyle and condylar head volume were also reliable, with the intraclass correlation coefficient (ICC) values of intra-observer 0.998/0.941 and inter-observer 0.999/0.942 respectively. The volumetric increment of the condyle and condylar head after treatment was (41.7±90.2) mm³ and (62.8±70.9) mm³, respectively. Eighty-two condyles were divided into three sub-groups: no remodeling (21), partial remodeling (20) and remarkable remodeling (41). Ranking of the volumetric increment of the condyle and condylar head after treatment was as follows: remarkable remodeling group>partial remodeling group>no remodeling group (P<0.05). Conclusions: The 3D quantitative measurement for evaluating condylar bone remodeling had excellent consistency and reliability, which was consistent with the qualitative classification for condylar bone remodeling. The condylar head as a region of interest was more sensitive to the volumetric changes.

[Association between tooth missing and non-alcoholic fatty liver disease].

Objective: To evaluate the association between the number of teeth missed and the prevalence of non-alcoholic fatty liver disease (NAFLD) in adults. Methods: A cross-sectional study was carried out in 26 983 adults from Tianjin Chronic Low-grade Systemic Inflammation and Health Cohort Study. The number of teeth missed (excluding third molars) was recorded and classified into four categories: 0, 1-, 3- and ≥6. NAFLD was diagnosed by at least two liver ultrasonography examinations. Adjusted multivariable logistic regression analysis was used to access the association between the number of missed teeth and NAFLD in adults. Results: The overall prevalence of NAFLD was 7 270 and the number of the subjects with at least one tooth missed was 9 667. The multivariable-adjusted ORs (95%CI) of NAFLD across the categories of tooth missing (0, 1-, 3- and ≥6) were as follows: 1.00, 1.04 (0.93-1.15), 1.08 (0.93-1.26) and 1.38 (1.09-1.76) (trend test P=0.030) in males; 1.00, 0.96 (0.82-1.12), 1.11 (0.91-1.35) and 1.22 (0.90-1.64) (trend test P=0.450) in females. Conclusion: The number of missed teeth was positively associated with a higher prevalence rate of NAFLD in males with over 6 teeth missed, but not in females.

Clinical protocol for managing acute disc displacement without reduction: a magnetic resonance imaging evaluation.

This study investigated the efficacy of a sequential combination of arthrocentesis, mandibular manipulation, and anterior repositioning splint (ARS) in the management of acute temporomandibular joint (TMJ) disc displacement without reduction (DDwoR). Twenty-one consecutive patients diagnosed with acute DDwoR by Diagnostic Criteria for Temporomandibular Disorders and magnetic resonance imaging (MRI) were recruited and managed with this method. Clinical and MRI data were obtained before and at 1 week after treatment. The disc-condyle relationship was determined by disc-condyle angle measurement. Condyle/disc positions were described as x-y coordinates with the summit of the articular fossa as the coordinate origin. Statistical analyses including independent/paired samples t-tests were conducted; significance was set at P<0.05. Clinical success was observed in 95.2% of patients (20/21) with 22 joints affected by acute DDwoR. After combined treatment and ARS insertion, TMJs with DDwoR showed (a) normal disc-condyle relationships with substantial forward and downward condyle movement and significant disc reduction in closed position, and (b) discs with an intermediate zone located between the condylar head and articular eminence in open position. The combined approach was highly effective in 'unlocking' acute TMJ DDwoR and achieving spatial full disc reduction and a normal disc-condyle relationship. The duration of acute DDwoR appears to be critical for success.

Association between hypoplastic condyles and temporomandibular joint disc displacements: a cone beam computed tomography and magnetic resonance imaging metrical analysis.

This study investigated the association between hypoplastic condyles and disc displacements without reduction (DDw/oR). Consecutive patients with non-syndromic unilateral condylar hypoplasia were recruited and clinical, cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI) data were acquired. Linear measurements including condylar head width, depth, height and condyle length were determined with CBCT while MRI was used to assess disc position, morphology and displacement. A total of 43 patients were enrolled of which 93.02% had a history of temporomandibular disorders (TMDs) and 83.72% presented with TMD signs and symptoms. Depth and height of the condylar head along with condyle length of hypoplastic joints (6.68±1.67mm, 4.97±1.25mm and 14.49±3.02mm, respectively) were significantly lesser than normal joints (7.77±1.26mm, 6.35±1.45mm and 18.20±3.18mm) (P<0.001). The prevalence of DDw/oR was significantly higher in hypoplastic joints (79.07% versus 13.95%) (P<0.001). Joints with hypoplastic condyles had shorter disc lengths (6.99 ± 2.16 mm vs, 8.45 ± 2.26 mm) (P=0.007). Furthermore, disc displacements were significantly more advanced (8.52 ± 2.84 mm) and severe (76.74% with severe translations) when compared to the contralateral side (4.77 ± 2.97 mm and 32.56%) (P<0.05). A significant association was observed between condylar hypoplasia and temporomandibular joint DDw/oR with hypoplastic joints exhibiting more severely displaced and deformed discs. DDw/oR coupled with repaired degenerative joint disease may mimic condylar hypoplasia radiographically.

[Computed tomographic features of desmoplastic ameloblastoma of the jaw].

OBJECTIVE: To retrospectively analyze the clinical and CT imaging features of desmoplastic ameloblastomas (DA) in comparison with other types of ameloblastomas. METHODS: Patients diagnosed with ameloblastoma histopathologically in Peking University School and Hospital of Stomatology from July 2000 to August 2017 were reviewed to analyze the constituent ratios and characteristics of DA. CT imaging features of DA (28 cases) were investigated in comparison with consecutive cases of solid/multicystic and unicystic ameloblastomas. The following imaging perspectives were analyzed: the border, internal structure, three-dimensional shape, tooth, the periodontium, the cortex and the expansion of the tumors. CT values were measured in the region of interest for quantitative analysis. RESULTS: Among the 1 269 cases of ameloblastomas, 50 (3.9%) were DA, which showed predilections for males (74.0%). The average age of DA was about 43.9 years old, which was higher than the other two types. The anterior incisorcanine region (62.0%) and premolar region (30.0%) were most frequently affected. The incidence rate of DA in mandibule was 56.0% (28/50), which was slightly higher than that of maxilla (44.0%). The DA characteristically showed scallop border and honeycomblike or soapbubble internal structure with bone formation on CT. The mean ratios of height to mesiodistal and buccal-lingual to mesio-distal distances were 0.76 and 0.63, which were higher than the other two types. According to the degree of internal bone formation, three subtypes of DA could be observed: densely ossifying type (I), honeycomb/soap bubble type (II) and sparsely ossifying type (III). The means and standard deviations of CT values of DA were significantly higher than those of the other two types, which were (488.8±164.0) HU (type I), (171.7±102.8) HU (type II), (42.1±8.8) HU (type III). CONCLUSION: CT is helpful for diagnosis of DA, which shows as solid tumor with varying degrees of internal ossification.

Adipose lipid turnover and long-term changes in body weight.

The worldwide obesity epidemic1 makes it important to understand how lipid turnover (the capacity to store and remove lipids) regulates adipose tissue mass. Cross-sectional studies have shown that excess body fat is associated with decreased adipose lipid removal rates2,3. Whether lipid turnover is constant over the life span or changes during long-term weight increase or loss is unknown. We determined the turnover of fat cell lipids in adults followed for up to 16 years, by measuring the incorporation of nuclear bomb test-derived 14C in adipose tissue triglycerides. Lipid removal rate decreases during aging, with a failure to reciprocally adjust the rate of lipid uptake resulting in weight gain. Substantial weight loss is not driven by changes in lipid removal but by the rate of lipid uptake in adipose tissue. Furthermore, individuals with a low baseline lipid removal rate are more likely to remain weight-stable after weight loss. Therefore, lipid turnover adaptation might be important for maintaining pronounced weight loss. Together these findings identify adipose lipid turnover as an important factor for the long-term development of overweight/obesity and weight loss maintenance in humans.

[Necessity and normalization of imaging examination on temporomandibular disorders].

Diagnosis and treatment of temporomandibular disorders (TMD) have been paid attention greatly by dentists in clinic. Imaging is the most important method for dentists to diagnose TMD correctly. Cone-beam CT (CBCT) and MRI have been demonstrated superiority and necessity that contribute to correctly diagnosis, early diagnosis and follow-up patients. However, there are several significant problems required for professional agreement: the procedures for CBCT and MRI examination need to be standardized; dentists have to be trained regularly for the knowledge of the imaging diagnosis of TMD; it should be emphasized that patient history and clinical examination are much more important for diagnosis, imaging is only a supplement and should not be over used.

[Characteristics of MRI and associated pathological features of the condylar cyst like lesions in temporomandibular joint].

Objective: To analyze the MRI characteristics and pathological features of the condylar cyst like lesions in temporomandibular joint (TMJ). Methods: The study was conducted retrospectively on TMJ images from 14 patients (2 males, 12 females, aged 10-71) who underwent MRI examinations, from January 2015 to December 2017 at Center for TMD and Orofacial Pain, Peking University School and Hospital of Stomatology including 2 patients with pathological results. The signals of the lesion, condylar bone and disc-condyle relationship were evaluated. Results: Cyst like lesions of 15 condyles from 14 patients were analyzed. All of the lesions showed hypersignal on T2WI (12/12), while most of them showed hypersignal on T1WI (8/11) and PDWI (11/12). Mostly the lesions were surrounded by hyposignal linear margin (12/15), with normal condylar bone signal (13/15). Disk displacement with reduction was discovered in 3 joints, while disk displacement without reduction was discovered in 8 joints and 4 joints had normal disk-condyle relationships. The pathological components of cyst like lesions included cartilage, loose connective tissue, hemorrhage and bone tissue. Conclusions: Differed from those of large joints like hips or knees, MRI characteristics of cyst like lesions of condyle in TMJ exhibited hypersignal imaging in both T1WI and T2WI, indicating that the components of cyst like lesions included granulation tissue, not fluid.

Functional characterization of ultraspiracle in Leptinotarsa decemlineata using RNA interference assay.

A heterodimer of ultraspiracle (USP) and ecdysone receptor (EcR) mediates 20-hydroxyecdysone (20E) signalling cascade to regulate insect moulting and metamorphosis. However, at least two questions remain to be addressed in terms of the molecular importance of USP in insect species. First, is USP involved in both regulation of ecdysteroidogenesis and mediation of 20E signalling in non-drosophilid insects, as in Drosophila melanogaster? Second, does USP play any role in larval metamorphosis except as the partner of heterodimeric receptor to activate the downstream 20E signalling genes? In this paper, we found that RNA interference (RNAi) of LdUSP in the final (fourth) instar larvae reduced the messenger RNA levels of four ecdysteroidogenesis genes (Ldspo, Ldphm, Lddib and Ldsad) and 20E titre, and repressed the expression of five 20E signal genes (EcRA, HR3, HR4, E74 and E75) in Leptinotarsa decemlineata. The LdUSP RNAi larvae remained as prepupae, with developing antennae, legs and discs of forewings and hindwings. Dietary supplement with 20E restored the expression of the five 20E signal genes, but only partially alleviated the decreased pupation rate in LdUSP RNAi beetles. Knockdown of LdUSP at the penultimate (third) instar larvae did not affect third-fourth instar moulting. However, silencing LdUSP caused similar but less severe impairments on pupation. Accordingly, we propose that USP is undoubtedly necessary for ecdysteroidogenesis, for mediation of 20E signalling and for initiation of metamorphosis in L. decemlineata.

Impairment of pupation by RNA interference-aided knockdown of Broad-Complex gene in Leptinotarsa decemlineata (Say).

Dietary delivery of bacterially expressed double-stranded RNA (dsRNA) has a great potential for management of Leptinotarsa decemlineata. An important first step is to discover possible RNA-interference (RNAi)-target genes effective against larvae, especially the old larvae. In the present paper, five putative Broad-Complex (BrC) cDNAs (Z1-Z4, and Z6) were identified in L. decemlineata. The expression of the five LdBrC isoforms was suppressed by juvenile hormone signaling, whereas the transcription was upregulated by 20-hydroxyecdysone signaling at the fourth (final) instar larval stage. Feeding of bacterially expressed dsBrC (derived from a common fragment of the five LdBrC variants) in the third- and fourth-instar larvae successfully knocked down the target mRNAs. For the fourth-instar LdBrC RNAi hypomorphs, they had a higher larval mortality compared with the controls. Moreover, most dsBrC-fed beetles did not pupate normally. After removal of the apolysed larval cuticle, a miniature adult was found. The adult head, compound eyes, prothorax, mesothorax, metathorax were found on the dorsal view. Distinct adult cuticle pigmentation was seen on the prothorax. The mouthparts, forelegs, midlegs, and hindlegs could be observed on the ventral view of the miniature adults. For the third-instar LdBrC RNAi specimens, around 20% moribund beetles remained as prepupae and finally died. Therefore, LdBrC is among the most attractive candidate genes for RNAi to control the fourth-instar larvae in L. decemlineata.

Isoform specific roles of Broad-Complex in larval development in Leptinotarsa decemlineata.

Broad-Complex (BrC) is a downstream target of both 20-hydroxyecdysone and juvenile hormone signalling. BrC regulates morphogenetic changes between nymphal instars in hemimetabolans, whereas it controls pupal commitment, pupal morphogenesis and inhibits adult differentiation in holometabolans. Among five BrC cDNAs (Z1-Z4 and Z6) identified in the Colorado potato beetle, we found in this work that Z1, Z2 and Z6 were mainly expressed at the last (fourth) instar and prepupal stages, whereas the levels of Z3 and Z4 increased during the penultimate (third) instar stage, peaked at the last instar larval phase and gradually decreased at the prepupal and pupal periods. When knocking down all BrC isoforms by RNA interference (RNAi) at the penultimate instar stage, around 20% of the resultant larvae remained as moribund beetles. These moribund BrC RNAi larvae were completely or partially wrapped in old cuticle. Likewise, a portion of larvae treated for a single double-stranded RNA of Z3, Z4 or Z6 displayed a degree of similar aberrancies, increasing in the order of isoforms Z6 < Z3 < Z4. When silencing all BrC isoforms at the last instar period, most of the RNAi larvae did not normally pupate or emerge as adults. Separately silencing each of the five zinc finger domains revealed that approximately 70% of the Z1 RNAi larvae remained as prepupae, around 60% of the Z6 RNAi specimens formed aberrant prepupae or pupae and about 60% of the Z2 RNAi beetles became deformed pupae. After removal of the old exuviae, these deformed larvae in which either Z1, Z2 or Z6 was depleted possessed adult prothorax and mesothorax, developing antenna, mouthparts and wing discs. Moreover, less than 50% of the resultant pupae finally emerged as adults when either of Z1, Z2 or Z6 was knocked down. Therefore, our findings reveal, for the first time, that the two roles of BrC in insect groups (ie directing morphogenetic changes during juvenile development and regulating larval-pupal-adult metamorphosis) are played by different BrC isoforms in Leptinotarsa decemlineata.

Silencing chitin deacetylase 2 impairs larval-pupal and pupal-adult molts in Leptinotarsa decemlineata.

Insect chitin deacetylases (CDAs) are carbohydrate esterases that catalyze N-deacetylation of chitin to generate chitosan, a process essential for chitin organization and compactness during the formation of extracellular chitinous structure. Here we identified two CDA2 splice variants (LdCDA2a and LdCDA2b) in Leptinotarsa decemlineata. Both splices were abundantly expressed in larval foregut, rectum, and epidermis; their levels peaked immediately before ecdysis within each instar. In vivo results revealed that the two isoforms transcriptionally responded, positively and negatively respectively, to 20-hydroxyecdysone and juvenile hormone signaling pathways. RNA interference (RNAi)-aided knockdown of the two LdCDA2 variants (hereafter LdCDA2) or LdCDA2b, rather than LdCDA2a, resulted in three negative effects. First, foliage consumption was significantly reduced, larval developing period was lengthened, and larval growth was retarded. Second, chitin contents were reduced, whereas glucose, trehalose, and glycogen contents were increased in the LdCDA2 and LdCDA2b RNAi larvae. Third, approximately 20% of LdCDA2 and LdCDA2b RNAi larvae were trapped within the exuviae and finally died. About 60% of the abnormal pupae died as pharate adults. Around 20% of the RNAi pupae emerged as deformed adults, with small size and wrinkled wings. These adults eventually died within 1 week after molting. Our results reveal that knockdown of CDA2 affects chitin accumulation. Consequently, LdCDA2 may be a potential target for control of L. decemlineata larvae.