REMINERALIZING POTENTIAL OF CALCIUM SUCROSE PHOSPHATE IN WHITE SPOT LESIONS: A SYSTEMATIC REVIEW.

BACKGROUND: This systematic review aimed to evaluate the remineralizing efficacy of calcium sucrose phosphate (CaSP) for the treatment of white spot lesions (WSLs) that commonly occur after orthodontic treatment with fixed appliances using various randomized controlled trials (RCTs) available in the literature to date. HIGHLIGHTS: Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines, RCTs that assessed the efficacious remineralizing potential of CaSP on WSLs and demineralized enamel and compared it with either no intervention or other remineralizing agents were selected. The methodological rigor of the included studies was subjected to the Risk of Bias tool-2 (ROB-2) and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) tools. Furthermore, a Begg's Funnel Plot was used to assess publication bias. The qualitative analysis encompassed a corpus of 36 studies. The remineralization potential of CaSP was investigated using an array of parameters, including surface microhardness, surface morphology, surface roughness, mineral content, and lesion size and depth. Based on the ROB-2 tool, most of the included studies were judged to be high risk, largely attributable to the presence of attrition bias. Using the GRADE framework, the certainty of evidence was determined to be moderate. CONCLUSION: This systematic review reveals that CaSP yields favorable outcomes in terms of increased surface microhardness and calcium-phosphate content, reduced demineralized area and surface roughness, and enhanced surface topography.

Detecting white spot lesions on post-orthodontic oral photographs using deep learning based on the YOLOv5x algorithm: a pilot study.

BACKGROUND: Deep learning model trained on a large image dataset, can be used to detect and discriminate targets with similar but not identical appearances. The aim of this study is to evaluate the post-training performance of the CNN-based YOLOv5x algorithm in the detection of white spot lesions in post-orthodontic oral photographs using the limited data available and to make a preliminary study for fully automated models that can be clinically integrated in the future. METHODS: A total of 435 images in JPG format were uploaded into the CranioCatch labeling software and labeled white spot lesions. The labeled images were resized to 640 × 320 while maintaining their aspect ratio before model training. The labeled images were randomly divided into three groups (Training:349 images (1589 labels), Validation:43 images (181 labels), Test:43 images (215 labels)). YOLOv5x algorithm was used to perform deep learning. The segmentation performance of the tested model was visualized and analyzed using ROC analysis and a confusion matrix. True Positive (TP), False Positive (FP), and False Negative (FN) values were determined. RESULTS: Among the test group images, there were 133 TPs, 36 FPs, and 82 FNs. The model's performance metrics include precision, recall, and F1 score values of detecting white spot lesions were 0.786, 0.618, and 0.692. The AUC value obtained from the ROC analysis was 0.712. The mAP value obtained from the Precision-Recall curve graph was 0.425. CONCLUSIONS: The model's accuracy and sensitivity in detecting white spot lesions remained lower than expected for practical application, but is a promising and acceptable detection rate compared to previous study. The current study provides a preliminary insight to further improved by increasing the dataset for training, and applying modifications to the deep learning algorithm. CLINICAL REVELANCE: Deep learning systems can help clinicians to distinguish white spot lesions that may be missed during visual inspection.

Incidence, severity, and risk factors for white spot lesions in adolescent patients treated with clear aligners.

OBJECTIVES: This study was aimed to clarify the incidence, severity, and clinical risk factors for white spot lesions (WSLs) in adolescent patients treated with clear aligners. METHODS: Pre-treatment and post-treatment intraoral photographs of 203 adolescent patients undergoing clear aligner therapy were retrospectively evaluated to assess the occurrence and severity of WSLs. Information on patients' general oral condition and orthodontic treatment was collected from clinical medical documents, retrospective questionnaires, and ClinCheck® software. Independent risk factors and model performance were determined by multivariate logistic regression and receiver operating characteristic curve analysis. RESULTS: Thirty-five percent of adolescent patients developed WSLs during clear aligner treatment. Logistic regression analysis revealed that the presence of WSLs before treatment (OR 2.484, 95% CI 1.245-4.957), frequency of drinking carbonated beverages (OR 1.508, 95% CI 1.045-2.177), and number of anterior attachments (OR 2.192, 95% CI 1.502-3.198) were risk factors for the occurrence of WSLs in adolescent patients treated with clear aligners (P < .05), whereas the number of times they brushed each day (OR 0.656, 95% CI 0.454-0.947) and frequency of aligner cleaning after eating while wearing them (OR 0.611, 95% CI 0.433-0.861) were protective factors against WSLs (P < .05). CONCLUSIONS: The incidence of WSLs was high in adolescent patients treated with clear aligners. Few brushings each day, pre-treatment WSLs, a high frequency of drinking carbonated beverages, a low frequency of aligner cleaning after eating while wearing them, and a high number of anterior attachments are strongly associated with the development of WSLs in adolescent patients treated with clear aligners.

Formulation of arginine-loaded mesoporous silica nanoparticles (Arg@MSNs) modified orthodontic adhesive.

OBJECTIVES: The objective of this study was to synthesize arginine loaded mesoporous silica nanoparticles (Arg@MSNs), develop a novel orthodontic adhesive using Arg@MSNs as modifiers, and investigate the adhesive performance, antibacterial activity, and biocompatibility. METHODS: Arg@MSNs were synthesized by immobilizing arginine into MSNs and characterized using transmission electron microscope (TEM), dynamic light scattering (DLS), and Fourier Transform Infrared Spectrometer (FT-IR). Arg@MSNs were incorporated into Transbond XT adhesive with different mass fraction to form functional adhesives. The degree of conversion (DC), arginine release behavior, adhesive performance, antibacterial activity against Streptococcus mutans biofilm, and cytotoxicity were comprehensively evaluated. RESULTS: TEM, DLS, and FT-IR characterizations confirmed the successful preparation of Arg@MSNs. The incorporation of Arg@MSNs did not significantly affect DC and exhibited clinically acceptable bonding strength. Compared to the commercial control, the Arg@MSNs modified adhesives greatly suppressed the metabolic activity and polysaccharide production while increased the biofilm pH values. The cell counting kit (CCK)-8 test indicated no cytotoxicity. CONCLUSIONS: The novel orthodontic adhesive containing Arg@MSNs exhibited significantly enhanced antibacterial activities and inhibitory effects on acid production compared to the commercial adhesive without compromising their bonding strength or biocompatibility. CLINICAL SIGNIFICANCE: The novel orthodontic adhesive containing Arg@MSNs exhibits potential clinical benefits in preventing demineralization of enamel surfaces around or beneath orthodontic brackets due to its enhanced antibacterial activities and acid-producing inhibitory effects.

Resin infiltration for white spot lesions: An in vitro experimental trial.

OBJECTIVE: To evaluate the aesthetic outcome by varying the duration allowed for infiltrant penetration when treating white spot lesions with resin infiltration. DESIGN: An in vitro, experimental randomised study. METHODS: Artificially created white spot lesions (WSLs) were induced on 100 extracted anterior teeth (T1). Teeth were divided into enamel and dentine groups depending on the extent of the lesion and then randomly assigned into different treatment protocol groups: penetration times of 3, 6 and 9 min. Resin infiltration treatment was applied according to the treatment protocol assigned (T2). Samples were thermocycled for 10,000 cycles (1 clinical year) (T3). The samples from the 3-min enamel and dentine groups were then randomly assigned into either a repeat treatment or no additional treatment group (T4). Samples were then thermocycled for an additional 10,000 cycles (T5). Spectrophotometric analysis was measured colour change (ΔE) for all groups. RESULTS: Mean ΔE values equal to or greater than the critical value (3.7) indicate a detectable clinical difference in colour of the treated WSL when compared to before WSL formation. Mean ΔE values, for the enamel groups, were slightly above or significantly below the critical value, and for the dentine groups, were significantly above the critical value. Mean ΔE values within the enamel and dentine groups both demonstrated a downward trend with increasing time allowed for resin infiltrant penetration (P < 0.05). No significant mean ΔE difference (P = 0.53) was found between groups that received a single or repeat treatment. After the first thermocycling event, no significant difference in colour change was observed in all groups except for the deep dentine lesion treated for 3 min. There was a significant difference in colour change for all groups except the enamel group that received a single treatment following thermocycling after a single or repeat treatment. CONCLUSION: Increasing the resin infiltrant penetration time to at least 9 min is advised as the most optimised treatment protocol. Resin infiltration treatment should be done only once to treat a particular white spot lesion as subsequent treatment for the same lesion results in marginal colour improvement. The colour improvement of WSLs resulting from the resin infiltration treatment can be expected to last for at least 1 year. Resin infiltration treatment of shallow lesions with a single and optimised infiltration technique can be expected to last an additional year.

White spot lesion-related perception of aesthetics and treatment satisfaction among orthodontic patients, orthodontists and other dental specialists.

OBJECTIVE: To investigate the impact of various degrees of white spot lesions (WSLs) of maxillary anterior teeth on the aesthetic perception and treatment satisfaction among orthodontic patients, orthodontists and other dental specialists and to evaluate the differences among the three groups. METHODS: A total of 45 orthodontic patients (OP), 45 orthodontists (OR) and 45 other dental specialists (OS) were recruited. Subjective evaluations of perceived aesthetics and treatment satisfaction were performed towards eight digitally generated photographs of maxillary anterior teeth with incremental degrees of WSLs using a numerical visual analogue scale (VAS) from 0 to 100. Data were collected and analysed with descriptive statistics, repeated one-way analysis of variance and multivariable generalized estimating equations. RESULTS: A total of 135 valid questionnaires were collected. Regarding aesthetic scores for WSLs, OP gave more positive scores than OR and OS (p < .05) towards excessive white spot formation without colouration and were more tolerant than OR (p < .05) towards excessive white spot formation with slight colouration. The level of treatment satisfaction for slight to severe WSLs without cavitation was higher in OP than OR. Patients with higher education levels had more negative scores for aesthetic perception and treatment satisfaction (p < .05). Patients who brushed teeth more frequently scored lower in treatment satisfaction (p < .05). CONCLUSIONS: Orthodontists were the most critical when evaluating aesthetics and treatment satisfaction for slight to severe WSLs without cavitation. For orthodontic patients, better oral hygiene habits and higher education levels were associated with more critical attitudes towards WSLs.

PHB2 inhibits WSSV replication by promoting the nuclear translocation of STAT.

Prohibitins (PHBs) are ubiquitously expressed conserved proteins in eukaryotes that are associated with apoptosis, cancer formation, aging, stress responses and cell proliferation. However, the function of the PHBs in immune regulation has largely not been determined. In the present study, we identified PHB2 in the red swamp crayfish Procambarus clarkii. PHB2 was found to be widely distributed in several tissues, and its expression was significantly upregulated by white spot syndrome virus (WSSV) challenge. PHB2 significantly reduced the amount of WSSV in crayfish and the mortality of WSSV-infected crayfish. Here, we observed that PHB2 promotes the nuclear translocation of STAT by binding to STAT. After blocking PHB2 or STAT with antibodies or interfering with PHB2 or STAT, the expression levels of the antiviral genes ß-thymosin (PcThy-4) and crustin2 (Cru2) decreased. The gene sequence of PHB2 was analyzed and found to contain a nuclear introgression sequence (NIS). After in vivo injection of PHB2 with deletion of NIS (rΔNIS-PHB2), the nuclear translocation of STAT did not change significantly compared to that in the control group. These results suggest that PHB2 promoted the nuclear translocation of STAT through NIS and mediated the expression of antiviral proteins to inhibit WSSV infection.

Prevalence of most caries-susceptible area on individual primary tooth surface: an observational study.

Due to multifactorial aetiology, tooth surfaces of primary dentition are more prone to dental caries and follow the specific pattern of dental caries which is difficult to control. The proper knowledge of caries-susceptible areas on individual primary teeth surfaces guides the clinician to take early preventive measures to stop the progression of dental caries. This study aims to find the prevalence of caries-susceptible areas on primary teeth surfaces in preschool children and the most commonly affected primary teeth. The study design adopted was a cross-sectional study. A total number of 3720 teeth of 186 preschool children were examined for initial pinpoint caries lesions using World Health Organization (WHO) caries detection criteria. 33 caries-susceptible areas were examined on individual primary tooth surfaces of preschool children who visited the Faculty of Dental Sciences. Each tooth surface was recorded separately and no radiographic examination was done. Obtained data was analysed keeping the level of significance at 5%. The overall prevalence of caries-susceptible area was found significantly higher in the maxillary teeth (Maxillary teeth: 41.7% vs. Mandible teeth: 30.7%; p < 0.001) and anterior teeth (Anterior teeth: 43.7% vs. Posterior teeth: 28.4%; p < 0.001). The prevalence of caries-susceptible area on primary teeth on the right side when compared to left counterparts was similar (Right side-38.6% and left side-38.4%; p = 0.931). Area 2 was the most prevalent area on primary teeth surfaces and primary canine was more prevalent in caries-susceptible areas.

Genome sequence of white spot syndrome virus (WSSV) infecting cultured black tiger shrimp (Penaeus monodon) in Bangladesh.

The white spot syndrome virus (WSSV) is a causative agent of white spot disease (WSD) in crustaceans, especially in cultivated black tiger shrimp (Penaeus monodon), leading to significant economic losses in the aquaculture sector. The present study describes four whole genome sequences of WSSV obtained from coastal regions of Bangladesh.

Fluoride-amorphous calcium phosphate and biomimetic nano-hydroxyapatite for enamel remineralization: An in-vitro study of surface microhardness and composition.

AIM: Fluoride-Amorphous Calcium Phosphate and Biomimetic Nano-Hydroxyapatite for Enamel Remineralization; An In-Vitro Study of Surface Microhardness and Composition. MATERIAL AND METHODS: Ninety-six extracted human premolars with sound buccal surface were divided using a randomization computer-generating software into four groups; Group I (control) sound untreated enamel, Group II (demineralized) demineralized to create white spot lesions, Group III (biom-n-HA) demineralized and then treated with biomimetic nanohydroxyapatite cream, and Group IV (F-ACP) demineralized and then treated using Fluoride-Amorphous Calcium Phosphate varnish. Each group was divided into two subgroups; subgroup "A" evaluated for mineral content using energy dispersive x-ray spectroscopy (EDX) and for surface microhardness using the Vickers microhardness test and Subgroup "B" evaluated for white spot lesion depth using a polarized light microscope (PLM). RESULTS: The highest microhardness (VHN) was found in the (F-ACP) group (mean=428.61±54.43) and then in the (Biom-n-HA) group (mean=408.11±70.16) followed by the (Control) group (mean=402.13±53.40) with no significant difference between them and finally in the significantly different (Demineralized) group (mean=256.99±45.83). The weight percentage of Ca (30.29±1.04 and 33.44±1.07) and Ca/P ratio (1.87±0.06 and 2.03±0.05) were significantly different between Group III and Group IV respectively. PLM measurements in Group II (198.83µm), Group III (60.17µm), and Group IV (26.33µm) were significantly different. CONCLUSIONS: Both the (Biom-n-HA) cream and the (F-ACP) varnish showed promising results for enamel remineralization. The increased enamel surface microhardness was consistent with the mineral content and the changes in the birefringence.

Evaluation of the remineralizing effect of the chicken eggshell paste after removal of the fixed orthodontic appliance: An in vitro study.

BACKGROUND: Demineralization of the enamel surface, which appears as white spot lesions during and after removal of the fixed orthodontic appliance, is the most common disadvantage of the orthodontic treatment course. Using the remineralizing agents during and after orthodontic treatment helps to avoid those enamel defects. OBJECTIVE: The present study aims to assess the remineralizing effect of the chicken eggshell powder on the demineralized enamel surfaces after debonding the orthodontic bracket system. MATERIALS AND METHODS: The current study was performed on 80 prepared premolar crowns embedded into acrylic molds. The samples were prepared to receive routine steps of the bonding process for the bracket system. The paste of the chicken eggshell powder was added to the samples after the debonding process. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) were used to evaluate the remineralization effect of the chicken eggshell powder. Also, the Vickers microhardness tester was used to assess the enamel surface microhardness. RESULTS: It was found that the mean value of the Ca/P ratio for the samples before bonding of the orthodontic bracket system was (4.17 ± 2.2). This value significantly decreased to (2 ± 1.3) after debonding of the orthodontic bracket system and then showed a significant increase to (4.79 ± 2.65) after remineralization. These results were assured by the values of the Vickers microhardness tester. CONCLUSION: The chicken eggshell powder has an excellent remineralization effect for the demineralized enamel surface after debonding the orthodontic enamel surface.

The effect of combined use of resin infiltration with different bioactive calcium phosphate-based approaches on enamel white spot lesions: An in vitro study.

OBJECTIVES: This in vitro study aimed to evaluate the effect of resin infiltration combined with casein phosphopeptide-amorphous calcium phosphate with fluoride (CPP-ACPF) or bioactive glass (BAG) on the stability of enamel white spot lesions (WSLs) treatment. MATERIALS AND METHODS: Eighty-four enamel blocks were prepared from the buccal surfaces of sound human premolars. All enamel blocks were placed in a demineralisation solution for 3 days to establish the artificial enamel WSLs. Enamel blocks with WSLs were randomly divided into three groups (n = 28 each group): RI/B: one-off resin infiltration followed by twice daily BAG treatment; RI/C: one-off resin infiltration followed by twice daily CPP-ACPF treatment; RI: one-off resin infiltration treatment only (as control) and subjected to pH cycling for 7 days. Surface morphology, elemental analysis, crystal characteristics, surface roughness and microhardness of enamel surfaces were investigated by scanning electron microscopy and energy-dispersive spectrometry observation, X-ray diffraction (XRD), atomic force microscope and Vickers' hardness testing, respectively. RESULTS: Mean values of the surface roughness (mean±standard deviation (nm)) were 24.52±5.07, 27.39±5.87 and 34.36±4.55 for groups RI/B, RI/C and RI respectively (p = 0.003). The calcium to phosphate ratios were 1.32±0.16, 1.22±0.26 and 0.69±0.24 for groups RI/B, RI/C and RI respectively (p < 0.001). XRD revealed apatite formation in all three groups. The mean enamel surface microhardness (kg/mm2) of the groups were 353.93±28.49, 339.00±27.32 and 330.38±22.55 for groups RI/B, RI/C and RI respectively (p = 0.216). CONCLUSIONS: Resin infiltration combined with CPP-ACPF or BAG remineralisation appears to improve the surface properties of WSLs. CLINICAL SIGNIFICANCE: The combination of resin infiltration and CPP-ACPF/BAG remineralisation may be a potential treatment for the management of the WSLs.

Antibacterial Activity and Shear Bond Strength of Orthodontic Adhesive Containing Various Sizes of Chitosan Nanoparticles: An In Vitro Study.

INTRODUCTION: White spot lesions are common after orthodontic treatment. Chitosan nanoparticles (CS-NPs) have emerged as promising antibacterial agents that inhibit the growth of Streptococcus mutans. The aim of the study was to investigate the nano-effect of adhesives containing CS-NPs on S. mutans and their effects on shear bond strength. MATERIALS AND METHODS: The inhibitory effects of two sizes of CS-NPs were assessed using the disc agar diffusion method. Four wells were created in the petri dishes, and each was inoculated with broth (negative control), chlorhexidine (positive control), CS-NPs (20 nm), or CS-NPs (131 nm). An Instron machine was used to evaluate shear bond strength by allocating 24 teeth into three groups, and all measurements were recorded in megapascals. Caries progression was assessed using the International Caries Detection and Assessment System and surface profilometry. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 27.0 (Released 2020; IBM Corp., Armonk, New York, United States) for a one-way ANOVA followed by Tukey's multiple comparison test. RESULTS: Disc agar diffusion showed a reduction in S. mutans in the CS-NP group compared to the control (p < 0.001), with no statistical significance between the sizes of 20 and 131 nm (p = 0.95). Regarding shear bond strength, no differences were recorded when adhesive-containing CS-NPs and the control were compared (p = 0.44). Additionally, no differences were found within the CS-NP groups (p = 0.91). Caries assessments showed excellent agreement, as indicated by a weighted kappa. Profilometry readings showed higher surface roughness in the control than in the CS-NP groups (p < 0.001), with no statistically significant difference between the CS-NP groups (p = 0.72). CONCLUSION: CS-NPs of both sizes tested had similar antibacterial effects. In addition, the incorporation of CS-NPs did not affect shear bond strength.

Insect cells of Spodoptera frugiperda support WSSV gene replication but not progeny virion assembly.

The lacking of stable and susceptible cell lines has hampered research on pathogenic mechanism of crustacean white spot syndrome virus (WSSV). To look for the suitable cell line which can sustain WSSV infection, we performed the studies on WSSV infection in the Spodoptera frugiperda (Sf9) insect cells. In consistent with our previous study in vitro in crayfish hematopoietic tissue cells, the WSSV envelope was detached from nucleocapsid around 2 hpi in Sf9 cells, which was accompanied with the cytoplasmic transport of nucleocapsid toward the cell nucleus within 3 hpi. Furthermore, the expression profile of both gene and protein of WSSV was determined in Sf9 cells after viral infection, in which a viral immediate early gene IE1 and an envelope protein VP28 exhibited gradually increased presence from 3 to 24 hpi. Similarly, the significant increase of WSSV genome replication was found at 3-48 hpi in Sf9 cells after infection with WSSV, indicating that Sf9 cells supported WSSV genome replication. Unfortunately, no assembled progeny virion was observed at 24 and 48 hpi in Sf9 cell nuclei as determined by transmission electron microscope, suggesting that WSSV progeny could not be assembled in Sf9 cell line as the viral structural proteins could not be transported into cell nuclei. Collectively, these findings provide a cell model for comparative analysis of WSSV infection mechanism with crustacean cells.

Aesthetic impact of resin infiltration and its mechanical effect on ceramic bonding for white spot lesions.

BACKGROUND: Treating white spot lesions (WSLs) with resin infiltration alone may not be sufficient, raising questions about its compatibility with other treatments amid controversial or incomplete data. Therefore, this study aimed to assess the aesthetic feasibility of resin infiltration combined with bleaching, as well as its potential mechanical effect on ceramic bonding to WSLs. METHODS: One hundred and fifty flat enamel surfaces of bovine incisors were prepared. Ninety specimens were deminerailized and randomly assigned to three groups(n = 30): post-bleaching resin infiltration (Bl-R), pre-bleaching resin infiltration (R-Bl), and only resin infiltration (R). Color, surface roughness and microhardness were assessed in immediate, thermocycling and pigmentation tests. The remaining sixty samples were randomly assigned to three groups (n = 20): control (Ctrl), bonding (Bo), pre-bonding resin infiltration (R-Bo). Shear bonding strength, failure mode, micro-leakage depth and interface morphology were evaluated after ceramic bonding. The Tukey test and analysis of variance (ANOVA) were used for statistical analysis. RESULTS: For the effect of resin infiltration and bleaching on WSLs, the R-Bl group showed the worst chromic masking ability, with the highest |ΔL|, |Δa|, |Δb|, and ΔE values after treatment. Compared with those in the Bl-R group, the R-Bl and R groups showed significant time-dependent staining, which is possibly attributed to their surface roughness. For the effect of resin infiltration on the adhesive properties of WSLs, resin infiltration reduced the staining penetration depth of WSLs from 2393.54 ± 1118.86 µm to 188.46 ± 89.96 µm (P < 0.05) while reducing WSLs porosity in SEM observation. CONCLUSIONS: Post-bleaching resin infiltration proved to be advantageous in the aesthetic treatment of WSLs. Resin infiltration did not compromise bonding strength but it did reduce microleakage and enhance marginal sealing. Overall, resin infiltration can effectively enhance the chromatic results of treated WSLs and prevent long-term bonding failure between ceramics and enamel. Based on these findings, the use of post-bleaching resin infiltration is recommended, and resin infiltration before ceramic bonding is deemed viable in clinical practice.

Ammonia stress-induced heat shock factor 1 enhances white spot syndrome virus infection by targeting the interferon-like system in shrimp.

Disease emergence is the consequence of host-pathogen-environment interactions. Ammonia is a key stress factor in aquatic environments that usually increases the risk of pathogenic diseases in aquatic animals. However, the molecular regulatory mechanisms underlying the enhancement of viral infection following ammonia stress remain largely unknown. Here, we found that ammonia stress enhances white spot syndrome virus infection in kuruma shrimp (Marsupenaeus japonicus) by targeting the antiviral interferon-like system through heat shock factor 1 (Hsf1). Hsf1 is an ammonia-induced transcription factor. It regulates the expression of Cactus and Socs2, which encode negative regulators of NF-κB signaling and Jak/Stat signaling, respectively. By inhibiting these two pathways, ammonia-induced Hsf1 suppressed the production and function of MjVago-L, an arthropod interferon analog. Therefore, this study revealed that Hsf1 is a central regulator of suppressed antiviral immunity after ammonia stress and provides new insights into the molecular regulation of immunity in stressful environments. IMPORTANCE: Ammonia is the end product of protein catabolism and is derived from feces and unconsumed foods. It threatens the health and growth of aquatic animals. In this study, we demonstrated that ammonia stress suppresses shrimp antiviral immunity by targeting the shrimp interferon-like system and that heat shock factor 1 (Hsf1) is a central regulator of this process. When shrimp are stressed by ammonia, they activate Hsf1 for stress relief and well-being. Hsf1 upregulates the expression of negative regulators that inhibit the production and function of interferon analogs in shrimp, thereby enhancing white spot syndrome viral infection. Therefore, this study, from a molecular perspective, explains the problem in the aquaculture industry that animals living in stressed environments are more susceptible to pathogens than those living in unstressed conditions. Moreover, this study provides new insights into the side effects of heat shock responses and highlights the complexity of achieving cellular homeostasis under stressful conditions.

Oral delivery of bacteria expressing wsv108 gene-specific dsRNA protects shrimp from white spot syndrome virus (WSSV) infection.

Double-stranded RNA (dsRNA) can specifically inhibit gene expression by RNA interference and has important application potential in animal disease control. White spot syndrome virus (WSSV) is one of the most harmful pathogens in shrimp aquaculture, causing huge economic losses every year. In this study, we investigated the function of the WSSV-encoded wsv108 protein. We demonstrated that wsv108 could promote apoptosis by interacting with heat shock protein 70 (HSP70) and enhancing the expression of multiple apoptosis-related genes. Silencing of wsv108 gene by injection with specific dsRNA prepared by in vitro transcription significantly increased the survival rate of WSSV-infected shrimp and reduced the viral load in tissues, suggesting that wsv108 is important for WSSV pathogenicity. Based on this, we expressed the wsv108 specific dsRNA in engineered Escherichia coli. Oral feeding of this bacterium could inhibit the expression of wsv108, increase the survival rate of WSSV-infected shrimp, and decrease the viral load of WSSV in tissues. Therefore, this study developed a new method for treatment of WSSV disease by oral administration of bacterially expressed dsRNA against a novel therapeutic target molecule, which could be a potential candidate strategy for WSSV control in aquaculture.

Distribution of initial caries lesions in relation to fixed orthodontic therapy. A systematic review and meta-analysis.

BACKGROUND: Initial caries lesion (ICLs) adjacent to orthodontic brackets are the most common side effect of orthodontic treatment with fixed appliances. The reported prevalence is uncertain and varies considerably across studies, from 27% to 97%. OBJECTIVES: This paper was designed to evaluate and synthesize the available evidence on the prevalence and incidence rates of ICLs in relation to orthodontic treatment. Selection criteria: The review (Prospero protocol CRD42023412952) included randomized and non-randomized clinical trials of interventions, cohort studies, and cross-sectional studies, published after 1990 on the prevalence or incidence of ICLs during or after orthodontic treatment with fixed appliances. Search methods: Pubmed, Scopus, and Embase databases were searched from 1990 until 01 May 2023. The risk of bias assessment was performed with RoB 2 and ROBINS-I tool and the Joanna Briggs Institute Critical Appraisal Checklist. Data collection and analysis: The proportion of individuals with ICLs, reported as the number/percentage of individuals/teeth with ICLs or mean number of ICLs per subject, were used to synthesize results. RESULTS: The search yielded a total of 468 papers; 21 studies were included in the systematic review, 2 of which were not included in the meta-analysis. The prevalence rate [95%CI] of ICLs was 0.57% [0.48; 0.65] in 1448 patients, 0.22% [0.14; 0.33] in 11583 teeth, with a mean number of lesions equal to 2.24 [1.79; 2.70] in 484 patients evaluated. The incidence rate of new carious lesions developed during orthodontic treatment was 0.48% [0.33; 0.63] in 533 patients, 0.15% [0.08; 0.26] in 1890 teeth with a mean number of ICLs equal to 2.29 [1.12; 3.46] in 208 patients evaluated. LIMITATIONS: Although the high number of included studies and the overall good quality, there was a significant heterogeneity in the collected data. CONCLUSION: The prevalence and incidence rates of ICLs in subjects undergoing orthodontic treatment are quite high and raise some concerns in terms of risk assessment of orthodontic treatment. ICLs represent an alarming challenge for both patients and professionals. Effective caries prevention strategies during treatment need to be considered and implemented where appropriate.

Vanillin-Mediated Green-Synthesised Silver Nanoparticles' Characterisation and Antimicrobial Activity: An In-Vitro Study.

Background and aim Nanoparticles in general due to their enhanced antimicrobial effects and other beneficial effects are used in dentistry. Silver nanoparticles (AgNPs) have emerged as the metal nanoparticle with the most advantages among the many types. The objective of the study was to synthesise vanillin-mediated AgNPs, then characterise those nanoparticles and assess their antimicrobial effectiveness. Materials and methods One-step synthesis of stable and crystalline AgNPs was done with vanillin as the reducing and capping agent. After being crushed into powder form, the produced AgNPs were subjected to characterisation. A scanning electron Microscope SEM) analysis was done for morphological details of the AgNPs. SEM with energy dispersive X-ray spectroscopy analysis (EDAX) and Fourier transform infrared (FTIR) testing were done for elemental analysis. AgNPs' antimicrobial properties were tested using the agar well diffusion technique. Results The SEM analysis revealed that the synthesized AgNps were porous and agglomerative clusters and varied in sizes between 30-35 nm. SEM-EDAX revealed the presence of 76.2 weight (wt)% Ag, 4.9 wt% carbon, and 18.9 wt% of oxygen. FTIR prominent peaks were observed at 1431.97 cm and 1361.20 cm indicating the presence of AgNPs. Both low and high concentrations of AgNps showed good antimicrobial effects against Streptococcus mutans (S. mutans). Conclusion Vanillin can be successfully used as a reducing agent for creating AgNPs. Due to their effective antimicrobial activity against S.mutans at various concentrations, vanillin-mediated AgNPs can be used with dental materials to reduce the risk of dental caries and enamel demineralization.

Biofilm volume and acidification within initial biofilms formed in situ on buccally and palatally exposed bracket material.

PURPOSE: Acidification by bacterial biofilms at the bracket/tooth interface is one of the most common problems in fixed orthodontic treatments, which can lead to white spot lesions (WSL) and caries. As lingual brackets were shown to exhibit reduced WSL formation clinically, the aim of this in situ study was to compare initial intraoral biofilm formation and acidification on bracket-like specimens placed buccally and palatally in the upper jaw as a possible cause for this observation. METHODS: Intraoral biofilm was collected from splints equipped with buccally and palatally exposed test specimens, which were worn by 12 volunteers for a total of 48 h. The test specimens consisted of standard bracket material cylinders on top of a hydroxyapatite disc to represent the bracket/tooth interface. They were analyzed for three-dimensional biofilm volume and live/dead distribution by fluorescence staining and confocal laser scanning microscopy as well as for acidification by fluorescence-based pH ratiometry. RESULTS: Similar general biofilm morphology with regard to volume and viability could be detected for buccally and palatally exposed specimens. For pH values, biofilms from both positions showed increased acidification at the bottom layer. Interestingly, the pH value at the top layers of the biofilms was slightly lower on palatally than on buccally exposed specimens, which may likely be due to anatomic conditions. CONCLUSION: Based on the results of this study, initial intraoral biofilm formation and acidification is almost similar on the bracket material/biomimetic tooth interface when placed buccally or palatally in the upper jaw. As lingual brackets were shown to exhibit reduced WSL formation clinically, future studies should investigate further factors like bracket geometry.