In vitro comparison of physical characteristics of milled versus printed zirconia discs.

PURPOSE: The purpose of this study was to compare the dimensional accuracy, translucency, and biaxial flexural strength of milled zirconia (MZ) versus 3D-printed zirconia (PZ) discs. MATERIALS & METHODS: A circular disc measuring 14.0 mm in diameter and 1.20 mm in thickness was designed using computer-aided design (CAD) software. The resulting standard tessellation language (STL) file was used both as a control and to fabricate 36 zirconia (3Y-TZP) disc specimens (n = 36): 18 were milled (group MZ) and 18 were 3D-printed (group PZ). The diameter and thickness of each disc were measured using a digital caliper. Translucency was evaluated using a calibrated dental colorimeter. The flexural strength was determined using the piston-on-three-ball biaxial flexure test. All measurements were done by one blinded examiner. The statistical significance level was set to α = 0.05. RESULTS: The MZ discs had significantly more accurate dimensions than the PZ discs in both diameter and thickness when compared to the control CAD software-designed disc. The MZ discs exhibited significantly higher translucency (translucency parameter (TP) = 16.95 ±0.36 vs. 9.24 ±1.98) and biaxial flexural strength (996.16 ±137.37 MPa vs. 845.75 ±266.16 MPa) than the PZ discs. Finally, MZ possessed a significantly higher Weibull modulus relative to PZ. CONCLUSIONS: The results showed that the milled specimens achieved better dimensional accuracy and were more translucent, stronger, and less prone to failure than printed specimens.

Bioengineering of Halobacterium sp. NRC-1 gas vesicle nanoparticles with GvpC fusion protein produced in E. coli.

Gas vesicle nanoparticles (GVNPs) are hollow, buoyant prokaryotic organelles used for cell flotation. GVNPs are encoded by a large gas vesicle protein (gvp) gene cluster in the haloarchaeon, Halobacterium sp. NRC-1, including one gene, gvpC, specifying a protein bound to the surface of the nanoparticles. Genetically engineered GVNPs in the Halobacterium sp. have been produced by fusion of foreign sequences to gvpC. To improve the versatility of the GVNP platform, we developed a method for displaying exogenously produced GvpC fusion proteins on the haloarchaeal nanoparticles. The streptococcal IgG-binding protein domain was fused at or near the C-terminus of GvpC, expressed and purified from E. coli, and shown to bind to wild-type GVNPs. The two fusion proteins, GvpC3GB and GvpC4GB, without or with a highly acidic GvpC C-terminal region, were found to be able to bind nanoparticles equally well. The GVNP-bound GvpC-IgG-binding fusion protein was also capable of binding to an enzyme-linked IgG-HRP complex which retained enzyme activity, demonstrating the hybrid system capability for display and delivery of protein complexes. This is the first report demonstrating functional binding of exogenously produced GvpC fusion proteins to wild-type haloarchaeal GVNPs which significantly expands the capability of the platform to produce bioengineered nanoparticles for biomedical applications. KEY POINTS: • Haloarchaeal gas vesicle nanoparticles (GVNPs) constitute a versatile display system. • GvpC-streptococcal IgG-binding fusion proteins expressed in E. coli bind to GVNPs. • IgG-binding proteins displayed on floating GVNPs bind and display IgG-HRP complex.

Characterization of a C-Type Lectin Domain-Containing Protein with Antibacterial Activity from Pacific Abalone (Haliotis discus hannai).

Genes that influence the growth of Pacific abalone (Haliotis discus hannai) may improve the productivity of the aquaculture industry. Previous research demonstrated that the differential expression of a gene encoding a C-type lectin domain-containing protein (CTLD) was associated with a faster growth in Pacific abalone. We analyzed this gene and identified an open reading frame that consisted of 145 amino acids. The sequence showed a significant homology to other genes that encode CTLDs in the genus Haliotis. Expression profiling analysis at different developmental stages and from various tissues showed that the gene was first expressed at approximately 50 days after fertilization (shell length of 2.47 ± 0.13 mm). In adult Pacific abalone, the gene was strongly expressed in the epipodium, gill, and mantle. Recombinant Pacific abalone CTLD purified from Escherichia coli exhibited antimicrobial activity against several Gram-positive bacteria (Bacillus subtilis, Streptococcus iniae, and Lactococcus garvieae) and Gram-negative bacteria (Vibrio alginolyticus and Vibrio harveyi). We also performed bacterial agglutination assays in the presence of Ca2+, as well as bacterial binding assays in the presence of the detergent dodecyl maltoside. Incubation with E. coli and B. subtilis cells suggested that the CTLD stimulated Ca2+-dependent bacterial agglutination. Our results suggest that this novel Pacific abalone CTLD is important for the pathogen recognition in the gastropod host defense mechanism.

Caregiver's difficulty paying child's healthcare bills and bullying victimization of adolescents with physical disabilities.

Guided by the ecological systems perspective, the objective of the study was to examine whether caregivers' difficulty paying their child's health-care bills is associated with bullying victimization directly and indirectly through the mediating mechanisms of caregivers' frustration, adolescents' internalizing problems, and social difficulty focusing on adolescents with physical disabilities. The 2019 National Survey of Children's Health dataset, which collected data on adolescents' and caregivers' demographic characteristics and health and well-being, was used. The study sample consisted of 368 caregivers of adolescents, 12-17 years of age with physical disabilities. No direct association between caregivers' difficulty paying their child's health-care bills and bullying victimization was found. However, caregivers' frustration and adolescents' internalizing problems were shown to have an indirect association with bullying victimization, which was mediated by difficulty making friends. In addition, adolescents' difficulty making friends was positively associated with bullying victimization. Practitioners working with adolescents with physical disabilities are encouraged to foster collaborative processes across various ecological systems of the adolescent and family to address caregivers' frustration and promote positive social and emotional development of the adolescent with physical disabilities, which can decrease their risk of bullying victimization.

In vitro shear bond strength of 2 resin cements to zirconia and lithium disilicate: An in vitro study.

STATEMENT OF PROBLEM: There is little evidence on how the multiple layers of zirconia (ZrO2) or glazed material will affect the shear bond strength (SBS) of different resin cements. PURPOSE: The purpose of this in vitro study was to compare the SBS of 2 resin cements with the different layers of a monolithic polychromatic ZrO2 ceramic, both glazed and nonglazed, and a lithium disilicate (LDS) ceramic. MATERIAL AND METHODS: One hundred and sixty-eight composite resin cylinders and 48 monolithic polychromic ZrO2 plates were prepared. Twenty-four were milled and sintered, and 24 were milled and sintered and had a glaze cycle applied with no liquid glaze. These plates and 12 LDS plates were mounted in autopolymerized acrylic resin. Bonding surfaces were polished, airborne-particle abraded, and cleaned ultrasonically. The different layers (cubic, hybrid, and tetragonal) of the ZrO2 plates were identified and marked. The plates were assigned to 2 cement groups: a self-adhesive, autopolymerized resin cement, and a dual-polymerizing, adhesive resin cement (DPRC). Bonding surfaces were cleaned and treated according to the cement manufacturer's instructions. Three composite resin cylinders were luted to the ZrO2 plates at the appropriate layer, and 2 cylinders were luted to each LDS plate. The specimens were stored in a moist environment for 24 hours at 37 °C. The SBS test was performed with a universal testing machine. Visual inspections of the debonded surfaces were compared under magnification. The data were analyzed with a 2-way ANOVA and a subsequent Student t test (α=.05). RESULTS: The 2-way ANOVA found no difference among luting agent and LDS and ZrO2. The SBSs of the nonglazed tetragonal and cubic layer to the ZrO2 were higher than to the surface exposed to a glazing cycle (P=.001). The bonded surfaces were examined tactilely and under ×3.5 magnification, followed by light and scanning electron microscopy and recorded as either adhesive, cohesive, or mixed. Almost all failures in the glazed ZrO2 were mixed and cohesive. However, more adhesive failures were observed in the DPRC group of nonglazed ZrO2. CONCLUSIONS: No differences were found between the 2 luting agents for the LDS. For the ZrO2 cubic and tetragonal layers, the DPRC had higher bond strengths to the nonglazed surfaces.

Heat shock protein 70 gene expression and stress response of red-spotted (Epinephelus akaara) and hybrid (E. akaara female × E. lanceolatus male) groupers to heat and cold shock exposure.

The importance of the temperature tolerance of fish is increasing due to climate change caused by global warming. This study examined the expression of the heat shock protein 70 (HSP70) gene, and plasma cortisol and glucose levels, as a stress response in red-spotted and hybrid groupers during exposure to heat and cold shock. Temperature in the tank where fishes acclimated at 20℃ was gradually increased or decreased, respectively, to examine the survival rate of fish. The result showed a higher survival rate of the hybrid than that of the red-spotted grouper upon exposure to a higher temperature. To further analyze the factors associated with temperature-associated stress, fishes were collected from different temperatures which changed from 20 to 30℃ or 10℃, respectively, and then back to 20℃. The expression levels of the gene encoding heat shock protein 70 (HSP70) were analyzed by qPCR using cDNA prepared from RNA extracted from the brain. A higher level of HSP70 transcript was detected in the hybrid during heat shock exposure. Analysis of cortisol and glucose from the blood of fish collected during the acclimation periods clearly indicated that the level of cortisol was increased upon temperature shift although a slight difference in the degrees of changes timing was slightly different between red-spotted grouper and hybrid. The results showed a correlation between the level of HSP70 and survival rate upon exposure to higher temperature shock. This study provides basic information regarding whether HSP70 expression increases the survival rate of fish subjected to rapid temperature changes.

Management of Amelogenesis Imperfecta in Adolescent Patients: Clinical Report.

The oral rehabilitation of adolescent patients with amelogenesis imperfecta (AI) is complex due to the presence of mixed dentition with altered eruption sequence. In this article, the interdisciplinary treatment approach for adolescent patients with AI is discussed. The types and timing of treatments at various stages of growth are described through a literature review on this topic. AI is an inherited condition that disturbs the development of the enamel structure. Because of the presence of mixed dentition, definitive treatment options often have to be delayed until eruption of permanent dentition is complete, requiring careful treatment coordination and proper sequencing between different dental disciplines starting at a young age. Adolescent patients require prosthodontic treatment design that can be adapted to the changes in arch shapes, sizes, interarch relationship, and esthetic needs. AI patients are often challenged with both excessive and limited restorative spaces within the same arch due to the abnormal growth patterns, enamel structure, tooth size, and tooth shape. Therefore, careful determination of the required restorative space is critical to ensure optimal prognosis. This clinical report discusses treatment recommendations, timing of various treatment modalities, and involvement of appropriate interdisciplinary teams for managing adolescent patients.

Defining centric relation.

STATEMENT OF PROBLEM: Multiple definitions of centric relation (CR) have evolved over time that may have created confusion or impeded understanding. A recent attempt to achieve a singular definition by surveying the members of the Academy of Prosthodontics (AP) did not achieve majority consensus. PURPOSE: The purpose of this study was to identify those aspects or attributes within the existing definitions of CR in which there was agreement or disagreement among the members of the AP. MATERIAL AND METHODS: After pretesting and institutional review board approval, a second survey of the AP membership was performed using both email and postal mail survey methods of contact. The CR Attributes Survey separated and stratified the previous definitions of CR into 5 domains: spatial relationship, condylar position, articular disks, mandibular movement, and recording. Each domain attribute was evaluated by agree-uncertain-disagree assessments. Also recorded were demographics, perception of scientific evidence, and open comments. RESULTS: Of the total 146 fellows, 100 completed the survey for an overall response rate of 68.5%. The query completion rate ranged from 96% to 98%. The CR Attributes Survey revealed those components within each domain in which there was strong agreement, disagreement, or uncertainty. The survey assessment of those queries with a moderate to strong agreement were that CR is a "spatial relationship" that is (1) a clinically determined relationship of the mandible to the maxilla, (2) a repeatable position, (3) is independent of tooth contact, and (4) is a physiologic position. Relative to "disks," the condyles articulate with the thinnest avascular intermediate zone of their respective disks; however, there is a lack of sufficient evidence to determine the position of the disks and the condyles. Relative to "mandibular movement," CR is (1) a starting point for vertical, lateral, or protrusive movements, (2) is where the individual can make to and from lateral movements, and (3) is restricted to pure rotary movement about a transverse horizontal axis. Relative to "recording CR" (1) it can be determined in patients without pain or derangement of the temporomandibular joints (TMJs), (2) but may not be recordable in the presence of dysfunction of the masticatory system, or (3) due to the neuromuscular influence or proprioception from the dentition, (4) is a clinical useful repeatable reference position for mounting casts, or (5) for developing a functional treatment occlusion, (6) at an established vertical dimension, and (7) may vary slightly by recording method. CONCLUSIONS: The CR Attributes Survey revealed a majority agreement or consensus for various CR attributes that should be considered for defining the term 'centric relation.' In contrast, those CR attributes with a plurality agreement, disagreement, or uncertainty outcomes should be considered for exclusion. The evaluated weakness of these latter attributes indicates the need for further research and reassessment.

A survey to determine agreement regarding the definition of centric relation.

STATEMENT OF PROBLEM: The definition of centric relation (CR) has been both controversial and divisive, with little consensus. PURPOSE: The purpose of this study was to determine whether agreement can be reached on a definition for CR among the Fellows of the Academy of Prosthodontics, the organization that writes the Glossary of Prosthodontic Terms. MATERIAL AND METHODS: A survey of the Fellows of the Academy of Prosthodontics was conducted at the organization's annual business meeting. RESULTS: Of the 83 eligible Fellows in attendance, 72 responded to the survey, a response rate of 86%. Of those, the 5 responders who did not indicate a preferred definition and the 2 that chose 2 definitions were censored, yielding an analyzable sample of 65 for the definitions. The most common definition received 19 votes, the next 16, and the third 13, with the other 6 definitions receiving from 2 to 5 votes. Some of the variability in definition depended on the era of training. CONCLUSIONS: Disagreement and confusion continues regarding the definition of centric relation. Some of this disagreement can be explained by training era.

Mandibular fibular graft reconstruction with CAD/CAM technology: A clinical report and literature review.

This clinical report describes the treatment of a partially dentate patient who presented with dental implants placed in a reconstructed fibula graft in the mandible. A complete mouth rehabilitation with a maxillary complete denture and a mandibular implant-supported fixed complete denture was fabricated with computer-aided design and computer-aided machining technology.

Dim-light photoreceptor of chub mackerel Scomber japonicus and the photoresponse upon illumination with LEDs of different wavelengths.

To study the absorption characteristics of rhodopsin, a dim-light photoreceptor, in chub mackerel (Scomber japonicus) and the relationship between light wavelengths on the photoresponse, the rod opsin gene was cloned into an expression vector, pMT4. Recombinant opsin was transiently expressed in COS-1 cells and reconstituted with 11-cis-retinal. Cells containing the regenerated rhodopsin were solubilized and subjected to UV/Vis spectroscopic analysis in the dark and upon illumination. Difference spectra from the lysates indicated an absorption maximum of mackerel rhodopsin around 500 nm. Four types of light-emitting diode (LED) modules with different wavelengths (red, peak 627 nm; cyan, 505 nm; blue, 442 nm; white, 447 + 560 nm) were constructed to examine their effects on the photoresponse in chub mackerel. Behavioral responses of the mackerels, including speed and frequencies acclimated in the dark and upon LED illumination, were analyzed using an underwater acoustic camera. Compared to an average speed of 22.25 ± 1.57 cm/s of mackerel movement in the dark, speed increased to 22.97 ± 0.29, 24.66 ± 1.06, 26.28 ± 2.28, and 25.19 ± 1.91 cm/s upon exposure to red, blue, cyan, and white LEDs, respectively. There were increases of 103.48 ± 1.58, 109.37 ± 5.29, 118.48 ± 10.82, and 109.43 ± 3.92 %, respectively, in the relative speed of the fishes upon illumination with red, blue, cyan, and white LEDs compared with that in the dark (set at 100 %). Similar rate of wavelength-dependent responses was observed in a frequency analysis. These results indicate that an LED emitting a peak wavelength close to an absorption maximum of rhodopsin is more effective at eliciting a response to light.

Differentially-Expressed Genes Associated with Faster Growth of the Pacific Abalone, Haliotis discus hannai.

The Pacific abalone Haliotis discus hannai is used for commercial aquaculture in Korea. We examined the transcriptome of Pacific abalone Haliotis discus hannai siblings using NGS technology to identify genes associated with high growth rates. Pacific abalones grown for 200 days post-fertilization were divided into small-, medium-, and large-size groups with mean weights of 0.26 ± 0.09 g, 1.43 ± 0.405 g, and 5.24 ± 1.09 g, respectively. RNA isolated from the soft tissues of each group was subjected to RNA sequencing. Approximately 1%-3% of the transcripts were differentially expressed in abalones, depending on the growth rate. RT-PCR was carried out on thirty four genes selected to confirm the relative differences in expression detected by RNA sequencing. Six differentially-expressed genes were identified as associated with faster growth of the Pacific abalone. These include five up-regulated genes (including one specific to females) encoding transcripts homologous to incilarin A, perlucin, transforming growth factor-beta-induced protein immunoglobulin-heavy chain 3 (ig-h3), vitelline envelope zona pellucida domain 4, and defensin, and one down-regulated gene encoding tomoregulin in large abalones. Most of the transcripts were expressed predominantly in the hepatopancreas. The genes identified in this study will lead to development of markers for identification of high-growth-rate abalones and female abalones.

Effect of initial salt concentrations on cell performance and distribution of internal resistance in microbial desalination cells.

Microbial desalination cells (MDCs) are modified microbial fuel cells (MFCs) that concurrently produce electricity and desalinate seawater, but adding a desalination compartment and an ion-exchange membrane may increase the internal resistance (Ri), which can limit the cell performance. However, the effects of a desalination chamber and initial NaCl concentrations on the internal resistances and the cell performances (i.e. Coulombic efficiency (CE), current and power density) of MDCs have yet to be thoroughly explored; thus, the cell performance and Ri distributions of MDCs having different initial concentrations and an MFC having no desalination chamber were compared. In the MDCs, the current and power density generation increased from 2.82 mA and 158.2 mW/m2 to 3.17 mA and 204.5 mW/m2 when the initial NaCl concentrations were increased from 5 to 30 g/L, as a consequence of the internal resistances decreasing from 2432.0 to 2328.4 Ω. And even though the MFC has a lower Ri than the MDCs, lower cell performances (current: 2.59 mA; power density: 141.6 mW/m2 and CE: 62.1%) were observed; there was no effect of improved junction potential in the MFC. Thus, in the MDCs, the higher internal resistances due to the addition of a desalination compartment can be offset by reducing the electrolyte resistance and improving the junction potential at higher NaCl concentrations.

Organizational justice and secondary traumatic stress among child welfare workers: The moderated mediation model.

OBJECTIVE: Secondary traumatic stress (STS) is documented as a common occupational hazard among child welfare workers. We examined the moderated mediation effects of distributive, procedural, and interpersonal justice on child welfare workers' STS. METHOD: We analyzed survey data collected from 1,053 child welfare workers in a Midwestern state in 2018. Participants were asked to rate their STS and perceived organizational justice using valid scales. Hypotheses were tested using multiple regression and the PROCESS macro. RESULTS: Distributive justice was a stronger factor associated with STS. The direct effect of procedural justice was not significant. However, it was associated indirectly with STS through distributive justice. Interpersonal justice was associated directly with STS. Furthermore, it moderated the association between distributive justice and STS. CONCLUSION: Findings suggest that the different types of organizational justice have different functions in reducing child welfare workers' STS. This study can contribute to developing justice-oriented and trauma-informed organizations that prevent child welfare workers' STS and reduce its negative effects on themselves, organizations, and children in the child welfare system. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Association between Secondhand Smoke and Allergic Diseases in Korean Adolescents: Cross-Sectional Analysis of the 2019 KYRBS.

This study aimed to determine whether secondhand smoking (SHS) in adolescents is associated with allergic diseases. Data from the 2019 Korea Youth Risk Behavior Survey were used (N = 37,848 Korean adolescents: 19,114 boys and 18,734 girls). This study assessed SHS exposure using questionnaire data, which included information, such as exposure to SHS and allergic diseases. Multiple logistic regression analysis was used to estimate the association between exposure to SHS and allergic diseases. The results showed that exposure to SHS in schools and public places, exposure for 1-3 days (OR = 1.158, 95% CI, 1.077-1.246), 4-6 days (OR = 1.308, 95% CI, 1.190-1.438), and everyday (OR = 1.306, 95% CI, 1.187-1.437), and exposure in one, two, or three places were significantly associated with allergic diseases (one OR = 1.226, 95% CI, 1.169-1.128, two OR = 1.289, 95% CI, 1.222-1.360 and three OR = 1.282, 95% CI, 1.177-1.395). The present results show that exposure to SHS occurs in various places and at various frequencies, and it is associated with allergic diseases in Korean adolescents.

State Child Maltreatment Policies and Disparities in Substantiation: A Study of State-Administered Child Welfare Systems in the U.S.

Although several studies have examined child and family factors associated with substantiation, less research has explored the role of state child maltreatment policies in substantiating cases of alleged maltreatment. In parallel, there is growing pressure to reduce racial/ethnic disproportionality and disparities across the span of a child welfare case. We examined the relationship between state child maltreatment policies and substantiation, with child race/ethnicity as a moderator of this relationship. Data came from the 2019 National Child Abuse and Neglect Data System (NCANDS) and the State Child Abuse and Neglect (SCAN) Policy Database. Using a series of multi-level binary logistic models, we calculated the odds of substantiation based on child characteristics (e.g., child age, number of types of alleged maltreatment) and state policies (e.g., state definitions of maltreatment that include exposure to domestic violence, harsh punishment). Approximately 17% of the variance in substantiation occurs between states. Although we did not find a direct effect of state policy on substantiation, there were significant interaction terms, in that inclusion of exposure to domestic violence, harsh punishment, or educational neglect in state policy was more strongly associated with substantiation for children of color than white children. Implications for policy and research are explored.

Ultrasound imagery for dental implant diagnosis and treatment planning in a porcine model.

STATEMENT OF PROBLEM: Currently, there is no commercially available method to provide non-invasive, non-ionizing, real-time imaging of the gingival form and bony architecture of implant sites, before, during, and after implant placement. PURPOSE: The purpose of this study was to demonstrate the feasibility of 2-dimensional (2-D) ultrasound imaging of soft and hard tissues for implant diagnosis and treatment planning. MATERIAL AND METHODS: A sector scanning ultrasound system was applied. Five representative clinical features (implant in an edentulous ridge, single implant tooth replacement, implant dehiscence, tooth dehiscence, and mental foramina) were created or identified in each of the 5 porcine jaws, which were then covered with soft tissue and imaged in an acoustic water tank. RESULTS: All of the 5 model features, in all 5 jaws, were clearly visible with the ultrasound. Most objects were visible over a large range of positions and angles. Each of the features, as well as the soft tissue and bone surfaces, were recognized by specific acoustic signatures, with the same signature recurring for each object type among all 5 of the jaw specimens. All implants were highly reflective and clearly visualized. CONCLUSIONS: A 2-D sector scanning ultrasound system was demonstrated to be capable of imaging representative features for implant treatment planning in a porcine model; these included implants placed in edentulous ridges; implants placed for single tooth replacement; implants with simulated dehiscences; teeth with simulated dehiscences; and mental foramina. Specific acoustic signatures for these features were defined. Qualitative differences between ultrasound and other dental imaging techniques were described.

Digital Analysis of the Dimensional Change Of an Irreversible Hydrocolloid Impression Material (Alginate) with Varying Storage Times.

AIM: The aim of this study was to digitally measure the dimensional changes in an irreversible hydrocolloid impression material (alginate) resulting from varying storage times under optimal storage conditions. MATERIALS AND METHODS: A single type V dental stone control cast was used to make 25 alginate impressions using perforated stock trays. The impressions were randomly assigned into five groups of five samples each (n=5 per group) with varying storage times: Group 1, poured at 15 minutes; Group 2, poured at one hour; Group 3, poured at 24 hours (one day); Group 4, poured at 72 hours (three days); Group 5, poured at 168 hours (seven days). All impressions were stored in sealed Ziploc® plastic bags with a wet paper towel (100% relative humidity) at room temperature and stored according to the assigned group storage times. All impressions were poured in type V dental stone according to the manufacturer's instructions. The casts were scanned with a digital 3D desktop scanner and saved as electronic stereolithography (.stl) files. Each .stl file of the scanned casts were superimposed on the .stl file of the control cast using Geomagic® Control X™ software. Three preselected fixed comparison measuring points (CMP) on each cast were compared to the control cast. Point one (CMP1) was on the midfacial surface of central incisor. Point two (CMP2) and point three (CMP3) were on the mesiobuccal proximal marginal ridge areas of third molars. The discrepancies between the files at each point were analysed with colour maps, and quantified (Table 1). The tolerance was set at ±10µm. CMP scores were analysed using one-way analysis of variance (ANOVA) and Kruskal-Wallis (K-W) non-parametric H tests. RESULTS: Average gap distances across groups ranged from 0.04mm (seven-day group) to 0.06mm (one hour and 24-hour groups). Colour maps indicated increased dimensional change with increased storage time up to one day. After three days, shrinkage up to 139µm was measured. ANOVA results for CMP1 (F[4,20] = 1.65, p = 0.020) and CMP3 (F[4,20] = 0.44, p = -0.78) were not statistically significant. Similarly, K-W results for CMP2 were not significant (χ2= 3.62, p = 0.46). CONCLUSIONS: Under optimal storage conditions, there were no significant dimensional changes in casts poured from alginate up to seven days.

Childhood Bullying Victimization, Substance Use and Criminal Activity among Adolescents: A Multilevel Growth Model Study.

BACKGROUND: This study aims to examine the effects of childhood bullying victimization (CBV) on substance use and criminal activity among adolescents over time. In addition, it identifies the moderating effects of gender and race/ethnicity on the associations of CBV with substance abuse and criminal activity in adolescence and young adulthood. METHODS: This study included 8984 adolescents aged 12 to 18 years (Mage = 14.22 years) assessed biennially at four time points utilizing the National Longitudinal Survey of Youth 1997. The two-level hierarchical linear modeling was employed to test the effects of CBV on substance use and criminal activity. RESULTS: The incidence of substance use increased over time throughout adolescence to young adulthood, while that of criminal activity decreased. CBV increased the risks of cigarette use, marijuana use, and criminal activity. Gender and race/ethnicity significantly moderated the effect of CBV on alcohol use and alcohol binges. The effect of CBV on alcohol use was stronger among females than males. Among Hispanic adolescents, CBV was more strongly related to alcohol use and binges compared to non-Hispanic White. CONCLUSION: Findings suggest the need for early intervention for children at high risk of being bullied to reduce later substance abuse and involvement in criminal activities. Considering the moderating effects of gender and ethnicity on the associations, target-specified intervention and prevention programs are also required. Further studies focusing on the lifelong effects of CBV beyond adolescence are recommended.