Automated facial landmark measurement using machine learning: A feasibility study.

STATEMENT OF PROBLEM: Information regarding facial landmark measurement using machine learning (ML) techniques in prosthodontics is lacking. PURPOSE: The objective of this study was to evaluate and compare the reliability, validity, and accuracy of facial anthropological measurements using both manual and ML landmark detection techniques. MATERIAL AND METHODS: Two-dimensional (2D) frontal full-face photographs of 50 men and 50 women were made. The interpupillary width (IPW), interlateral canthus width (LCW), intermedial canthus width (MCW), interalar width (IAW), and intercommissural width (ICW) were measured on 2D digital images using manual and ML methods. The automated measurements were recorded using a programming language (Python), and a convolutional neural network (CNN) model was trained to detect human facial landmarks. The obtained data from the manual and ML methods were analyzed using intraclass correlation coefficients (ICCs), the paired sample t test, Bland-Altman plots, and the Pearson correlation analysis (α=.05). RESULTS: Intrarater and interrater reliability values were greater than 0.90, indicating excellent reliability. The mean difference between the manual and ML measurements of IPW, MCW, IAW, and ICW was 0.02 mm, while it was 0.01 mm for LCW. No statistically significant differences were found between the measurements obtained by the manual and ML methods (P>.05). Highly significant positive correlations (P<.001) were obtained between the results of the manual and ML methods: (r=0.996[IPW], r=0.977[LCW], r=0.944[MCW], r=0.965[IAW], and r=0.997[ICW]). CONCLUSIONS: In the field of prosthodontics, the use of ML methods provides a reliable alternative to manual digital techniques for carrying out facial anthropometric measurements.

Evaluation of the parameters related to the golden ratio in the teeth of individuals from different countries: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Golden proportion, golden percentage, and recurring esthetic dental (RED) proportion are parameters used in esthetic dentistry. However, a meta-analysis of studies evaluating these parameters in individuals from different countries is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to determine and compare the golden ratio, golden percentage, and RED ratio values as seen in the maxillary anterior teeth of individuals from different countries. MATERIAL AND METHODS: A systematic search was performed using PubMed/Medline, Google Scholar, and Web of Science to identify English and non-English language articles reporting the golden proportion, golden percentage, and RED proportion. The titles, full text, and abstracts were scanned by 2 investigators independently to identify articles that fulfilled the inclusion criteria. Using a meta-analysis software program, data extracted from each selected study were statistically combined using the random-effects model. Weighted mean differences, 95% confidence intervals, and heterogeneity were calculated for each measurement. RESULTS: The search protocol resulted in a total of 752 articles, but only 26 articles fulfilling the inclusion criteria were included in the meta-analysis. While the sample size varied between 46 and 384 in the 26 analyzed studies, a total of 3786 individuals from 12 countries were evaluated. No similarity was found using the esthetic parameters determined in the populations to which the meta-analysis was applied. CONCLUSIONS: Mathematical formulas did not provide consistent results that would allow for their use as a standardized guide for creating natural looking smiles. Rather, dental esthetic ratios should be set based on the racial and ethnic character of a population.

Machine learning model to predict the width of maxillary central incisor from anthropological measurements.

PURPOSE: To improve smile esthetics, clinicians should comprehensively analyze the face and ensure that the sizes selected for the maxillary anterior teeth are compatible with the available anthropological measurements. The inter commissural (ICW), interalar (IAW), intermedial-canthus (MCW), interlateral-canthus (LCW), and interpupillary (IPW) widths are used to determine the width of maxillary central incisors (CW). The aim of this study was to develop an automated approach using machine learning (ML) algorithms to predict central incisor width in a young Turkish population using anthropological measurements. This automation can contribute to digital dentistry and clinical decision-making. METHODS: In the initial phase of this cross-sectional study, several ML regression models-including multiple linear regression (MLR), multi-layer-perceptron (MLP), decision-tree (DT), and random forest (RF) models-were validated to confirm the central width prediction accuracy. Datasets containing only male and female measurements, as well as combined were considered for ML model implementation, and the performance of each model was evaluated for an unbiased population dataset. RESULTS: Compared with the other algorithms, the RF algorithm showed improved performance for all cases, with an accuracy of 96%, which represents the percentage of correct predictions. The plot reveals the applicability of the RF model in predicting the CW from anthropological measurements irrespective of the candidate's sex. CONCLUSIONS: These results demonstrated the possibility of predicting central incisor widths based on anthropometric measurements using ML models. The accurate central incisor width prediction from these trials also indicates the applicability of the proposed model to be deployed for enhanced clinical decision-making.

Relationship between Antibody Levels and SARS-Cov-2 Reinfection.

OBJECTIVE: In this period when mutant strains are increasing all over the world, studies on how much humoral immunity will protect against the Severe Acute Respiratory Syndrome 2 (SARS-CoV-2) are quite limited. The aim of our study is to investigate the positivity and antibody levels of the COVID-19 reverse transcription polymerase chain reaction (RT-PCR) test, the frequency of SARS-CoV-2 re-infection, and the protective antibody level against re-infection. METHODS: Patients who were positive for COVID-19 IgG antibody between 1 July and 31 August were included in our study. The COVID-19 RT-PCR test positivity, age, gender and comorbidities of these patients were recorded before this date. The COVID-19 RT-PCR test positivity of these patients was followed from the National COVID-19 Database between September 1, 2020 and February 28, 2021. RESULTS: 1665 patients (female: male 683: 982, mean age 40.6±13.4 years). Among all patients, 14 patients had reinfection and the frequency of reinfection was 0.8%. It was observed that the frequency of reinfection was more frequent in patients with PCR negative (p<0.001). The IgG cut-off value causing reinfection was found to be 11.9 (AUC: 0.844, 79.2% sensitivity, 78.6% specificity) (p<0.001). CONCLUSION: Humoral antibodies against SARS-CoV-2 were protective against COVID-19 reinfection, 0.8% of the patients had reinfection and the resultant reinfection was mostly seen in PCR negative patients who were asymptomatic.

Effects of multiple firing processes on the mechanical properties of lithium disilicate glass-ceramics produced by two different production techniques.

STATEMENT OF PROBLEM: Repeated firings cause materials to be exposed to additional heat treatments. The effect of these additional heat treatments on the mechanical properties of lithium disilicate glass-ceramics is not fully known. PURPOSE: The purpose of this in vitro study was to determine the effects of repeated firing on the mechanical properties of lithium disilicate glass-ceramics produced by 2 different techniques, press and computer-aided design and computer-aided manufacturing (CAD-CAM). MATERIAL AND METHODS: Eighty rectangular (25×4×2 mm) lithium disilicate glass-ceramic specimens were used in this study, 40 produced by heat pressing and 40 by milling, and divided into 4 groups (n=10) with a different number of veneer porcelain firings (1 to 4). After firing, the Vickers hardness, flexural strength (3-point bend test), and fracture toughness were determined, and the specimens were analyzed with an environmental scanning electron micrograph. Data were analyzed with analysis of variance (ANOVA) (α=.05). RESULTS: The repeat firing processes did not affect the flexural strength of the specimens in either group (P>.05), while the surface hardness and fracture toughness were significantly changed (P<.05). CONCLUSIONS: Increasing the number of firings adversely affected the mechanical properties of lithium disilicate glass-ceramics.

The effects of repetitive firing processes on the optical, thermal, and phase formation changes of zirconia.

PURPOSE: The aim of this study was to investigate the effect of different numbers of heat treatments applied to superstructure porcelain on optical, thermal, and phase formation properties of zirconia. MATERIALS AND METHODS: Forty zirconia specimens were prepared in the form of rectangular prism. Specimens were divided into four groups (n = 10) according to the number of firing at heating values of porcelain. Color differences and translucency parameter were measured, and X-ray diffraction (XRD) analysis and differential scanning calorimetry (DSC) were performed. Data were analyzed with analysis of variance (ANOVA). RESULTS: There were no statistically significant differences in ΔE, TP, L, a, and b value changes of the zirconia specimens as a result of repetitive firing processes (P>.05). CONCLUSION: Although additional firing processes up to 4 increase peak density in thermal analysis, additional firing processes up to 4 times can be applied safely as they do not result in a change in color and phase character of zircon frameworks.

Association between serotonin 2A receptor (HTR2A), serotonin transporter (SLC6A4) and brain-derived neurotrophic factor (BDNF) gene polymorphisms and citalopram/sertraline induced sexual dysfunction in MDD patients.

Sexual dysfunction (SD) is a troublesome adverse effect of selective serotonin reuptake inhibitors (SSRIs). A variety of mechanisms might be involved in the occurrence of SD but the exact mechanism is still not clear. Genetic variations among patients treated with SSRIs are strong determinants of intolerance and poor compliance. The present study aimed to determine the relationship between serotonin-2A receptor (HTR2A) gene -1438A/G and 102T/C polymorphisms, serotonin transporter gene (SLC6A4) 5-HTT-linked polymorphic region (5-HTTLPR) insertion/deletion variant and brain-derived neurotrophic factor (BDNF) gene Val66Met polymorphisms and the occurrence of SD adverse effect in major depressive disorder patients treated with citalopram (CIT) or sertraline (SERT). The result from this investigation revealed that the -1438A/G and 102T/C polymorphisms appear to be associated with the SD induced by CIT. It was also demonstrated that patients receiving SERT, carrying T allele of HTR2A or L allele of 5-HTTLPR more likely to experience SD. Most important overall finding of the study is the combined effects of -1438A/G, 102T/C, and 5-HTTLPR polymorphisms. In a logistic regression model, the occurrence of SD increased with the number of risky alleles. As compared with subjects receiving SERT with few risky (≤2) alleles, those with had 5-6 alleles had an increased SD risk. After all, according to these findings, -1438A/G, 102T/C, and 5-HTTLPR polymorphisms could be considered as promising pharmacogenetic biomarkers in CIT/SERT treatment in major depressive disorder (MDD) patients to avoid the occurrence of SD.

Evaluation of the effect of storage time and disinfectant solutions on the dimensional accuracy of impression materials with digital radiography.

BACKGROUND: The dimensional accuracy of impression materials has been evaluated for a long time, but thus far, digital radiography has not been used for this purpose. The dimensional accuracy of impression materials is very important for the final adaptation of dental prostheses. OBJECTIVES: The objective of this study was to evaluate the effects of different disinfectant solutions and storage times on the dimensional stability of different impression materials by means of digital radiography. MATERIAL AND METHODS: Polyether (PE), hydrocolloid (IH), condensation silicone (CS), and addition silicone (AS) materials were used for preparing impressions, taken from an acrylic master model with 2 vertical and 2 horizontal reference points. Water (W), sodium hypochlorite (SH) and a disinfectant solution without aldehyde (Z) were applied on the impressions. Half of the impressions were poured over immediately and half of them - 1 day after. Digital radiography was used to determine the dimensional accuracy of the impression materials. The data was analyzed with a variance analysis and Tukey's multiple comparison test. RESULTS: While PE showed the smallest dimensional changes, IH showed the greatest in all lines. Applying SH and pouring 1 day after caused the greatest dimensional changes in all impression materials. CONCLUSIONS: Different disinfectant solutions and storage times had a different effect on the impressions, but the dimensional changes were clinically acceptable.

Relationship between different points on the face and the width of maxillary central teeth in a Turkish population.

STATEMENT OF PROBLEM: Dentists may have difficulty determining the appropriate widths of the maxillary central incisors (CW) when restoring teeth for patients with edentulism. Anthropological measurements can help. PURPOSE: The purpose of this observational study was to evaluate the relationship between different anthropological distances on the face and the CW in a young Turkish population. MATERIAL AND METHODS: A total of 210 Turkish dental students without dental and facial deformities participated in this study. Two different digital photographs of their face (relaxed and smiling) were taken. The intercommissural width (ICW), intermedial canthus width (MCW), interlateral canthus width (LCW), interpupillary width (IPW), interalar width (IAW), and CW were measured. The t test, Pearson correlation analysis, and multiple linear regression analysis were performed to determine the relationship between facial measurements and CW (α=.05). RESULTS: A significant correlation was found between facial measurements (r=0.516[ICW], r=-0.534[IAW], r=-0.639[MCW], r=-0.599[LCW], and r=-0.683[IPW]) and CW in both sexes. All facial measurements, except ICW and IPW in women and MCW in men, had a significant effect on CW according to the multiple linear regression analysis. CONCLUSIONS: IAW and LCW can be used to determine CW in both sexes. The ICW and IPW can be specific anthropological measurements for men, and the MCW can be a specific anthropological measurement for women to determine CW.

Effect of MDP-Based Silane and Different Surface Conditioner Methods on Bonding of Resin Cements to Zirconium Framework.

PURPOSE: To determine the shear bond strength (SBS) between zirconium framework and resin cements after different surface conditioner methods and after application of 10-methacryloyloxydecyl dihydrogen phosphate (MDP) based silane and a bonding agent mix. MATERIALS AND METHODS: 128 disc-shaped zirconium-oxide specimens were prepared. Specimens were placed in autopolymerizing acrylic resin. The bonding surface of specimens was smoothed consecutively with 600-, 800-, and 1200-grit silicon carbide papers under water cooling. Eight groups were prepared: CJ, Co-Jet; N, Nd-YAG laser; E, Er-YAG laser; NS, Nd-YAG laser + silane; ES, Er-YAG laser + silane; CJB, Co-Jet + bonding agent; NSB, Nd-YAG laser + silane + bonding agent; ESB, Er-YAG laser + silane + bonding agent. SEM analysis was performed under 2000× magnification. Dual- and self-cured resin cements were bonded to specimens, and shear force was applied. Data were analyzed with one-way ANOVA and Tukey's multiple comparison test (p < 0.05). RESULTS: The SBS values differed from each other among the groups. While the CJB group showed the highest values, the N group showed the lowest. The treatment with MDP-based silane and bonding agent mix increased SBS values of each cement belonging to each group. SB values of dual-cure resin cement were higher than those of self-cure resin cements. CONCLUSION: Different surface conditioner methods exhibit an important effect on the SBS of resin cements to zirconium. The application of MDP-based silane and bonding agent mix enhanced SB values.

The Effect of Laboratory Procedures and Repeated-glazing on Color of Metal-ceramic Restoration.

BACKGROUND: Routine laboratory procedures and repeated glazed effect the final color of metal-ceramic restorations (MCRs). Clinicians wonder if the color changes after routine laboratory procedures and repeated glazed is clinically acceptable or not. AIMS: The aim of this study was to determine the color changes of MCRs after routine laboratory procedures and then glazed for 1, 2, and 3 times. MATERIALS AND METHODS: Forty-five disc-shaped (10-mm diameter and 1-mm thickness) specimens were fabricated from Cr-Co metal-alloy. Bonding agent, first and second layer of shade A2 opaque porcelain (OP) were applied on the metal specimens. The color of specimens was measured with a spectrophotometer after each procedure and △E1, △E2, and △E3 values were calculated. Shade A2 feldspathic porcelain was applied (2-mm thickness) to all specimens. Glaze was applied on the porcelain for 1, 2, and 3 times and then, the color measured after each procedure and △E4, △E5, and △E6 values were calculated. Data were analyzed with one-way ANOVA and Duncan test (P < 0.05). RESULTS: △E1 that was obtained between the first layer of OP and bonding agent showed the greatest value. △E2 that was obtained between the second and first layer of OP showed the lowest value. After repeated glazed procedures, the final color of the specimens was changed; but, these changes were clinically acceptable (△E < 5.5). CONCLUSIONS: The routine laboratory procedures and glazed for 1,2, and 3 times is effect the color of MCRs; but, the color changes were clinically acceptable (△E < 5.5).

The relationship between the serotonin 2A receptor gene -1438A/G and 102T/C polymorphisms and citalopram/sertraline-induced nausea in major depressed patients.

OBJECTIVE: The aim of the present study was to determine the relationship between the polymorphisms of -1438A/G and 102T/C in the 5-HT2A receptor (HTR2A) gene and nausea/vomiting as a side effect induced by sertraline (SERT) or citalopram (CIT) in patients with major depressive disorder. METHODS: A total of 128 patients were enrolled, 63 patients received CIT, whereas 65 patients were treated with SERT. Nausea/vomiting were assessed with the UKU Side-effects Rating Scale at baseline and at the end of the second and fourth weeks. Polymerase chain reaction-restriction fragment length polymorphism technique was employed to determine genetic differences. RESULTS: We have found that, in the patients treated with CIT, there was a nominally significant difference in the genotypic distribution associated with -1438A/G polymorphism between patients with and without nausea (X2  = 6.15, p = 0.041). Moreover, logistic regression analysis revealed a significant association between nausea/vomiting as a side effect and -1438A/G polymorphism. That is, patients with the G allele were at a higher risk for developing nausea/vomiting (p = 0.044, odds ratio = 2.213). The 102T/C polymorphism in the HTR2A gene had no significant effect on the nausea/vomiting as a side effect among participants treated with either CIT or SERT. CONCLUSION: The present study suggests the association of the HTR2A gene -1438A/G polymorphism with nausea/vomiting as a side effect related to CIT treatment.

Bond Strength of Resilient Lining Materials to Denture Base Resin: A Systematic Review and Meta-Analysis.

PURPOSE: Bond strength of resilient lining materials with denture base materials is continuously under development. The purpose of this systematic review is to perform a meta-analysis to find out which form of resilient lining bonds better to the denture base, what surface treatments have the highest efficacy to increase the bonding, and what is the most commonly preferred test method to measure bond strength. MATERIALS AND METHODS: Based on a search of PubMed, EMBASE, and Google Scholar, 57 articles were included in this study. A meta-analysis was performed on the results of the 57 articles. RESULTS: The most commonly used test method was the tensile test. Effective surface treatments for bond strength vary depending on the type of the test applied and the type of the attached resilient lining material. Silicone-based resilient lining materials are more commonly preferred than acrylic-based resilient lining materials. While chemical agents and chemicals of resilient lining materials were the most commonly applied surface treatments, a very limited number of studies preferred applying CoJet and laser. CONCLUSIONS: The efficacy of surface treatments varies depending on the resilient lining materials and the test type. More successful results can be achieved by selecting the appropriate surface treatment according to the type of the resilient lining material to increase the bond strength. In particular, when used alone, laser appears to be more effective. Chemical agents and laser are the most effective surface treatments for both silicone- and acrylic-based liners. Moreover, new studies are required to determine the efficacy of CoJet. These findings should help clinicians select a suitable surface treatment to increase the bond strength of resilient lining materials to denture base materials.

An investigation of the esthetic indicators of maxillary anterior teeth in young Turkish people.

STATEMENT OF PROBLEM: Comprehensive studies evaluating the dimensions of anterior maxillary teeth in the Turkish population with respect to different esthetic parameters are lacking. PURPOSE: The purpose of this clinical study was to evaluate different proportions of teeth and compare them with current esthetic parameters such as the golden proportion, recurring esthetic dental proportion, and width-to-height ratio of central incisors and to evaluate whether the apparent contact dimension of maxillary anterior teeth follows the "50:40:30" rule. MATERIAL AND METHODS: A total of 150 Turkish dental students (81 men and 69 women) aged between 18 and 24 years participated in the study. Standardized digital photographs of the mouth were made from an anterior view. The width and length of the maxillary central incisor, apparent width of the maxillary lateral and canine teeth, and distances between contact areas of the maxillary incisor teeth were measured with software. Differences between the measured proportions and the determined esthetic parameters were assessed with the 1-sample t test (α=.05). RESULTS: The width and length proportions of the maxillary incisor teeth in both sexes were significantly different than the golden and recurring esthetic dental proportions. The width-to-height ratio for the maxillary central incisor was different from 80%, which is considered optimal, and the difference among these parameters was statistically significant (P<.001). The apparent contact dimensions on the right and left sides were not statistically significantly different (P>.05). However, the proportions did not fit the 50:40:30 ratio that has been defined as the esthetic proportion, and the differences were statistically significant (P<.001). CONCLUSION: Proportions among maxillary anterior teeth were found to be significantly different from the golden proportion and recurring esthetic dental proportion in both sexes. The proportions of apparent contact dimension were significantly different than the 50:40:30 ratio in both sexes. The width-to-height ratio for maxillary central incisor was significantly different from 80% in both sexes.

The effect of heat treatments applied to superstructure porcelain on the mechanical properties and microstructure of lithium disilicate glass ceramics.

The aim of this study was to investigate that heat treatments with different numbers applied to superstructure porcelain whether effects microstructure and mechanical properties of lithium disilicate ceramic (LDC). Eighty disc-shaped specimens were fabricated from IPS e.max Press. Specimens were fired at heating values of porcelain in different numbers and divided four groups (n=5). Initial Vickers hardness were measured and X-ray diffraction (XRD) analysis was performed. Different surface treatment were applied and then Vickers hardness, surface roughness and environmental scanning electron microscopy (ESEM) analysis were performed. Data were analyzed with Varyans analysis and Tukey HSD test (α=0.05). Initial hardness among groups was no significant different (p>0.05), but hardness and surface roughness after surface treatments were significant different (p<0.05). Lithium disilicate (LD) peaks decrease depended on firing numbers. ESEM observations showed that firing number and surface treatments effect microstructure of LDC. Increasing firing numbers and surface treatments effect the microstructure of LDC.

Genotype and Allele Frequency of CYP3A4 -392A>G in Turkish Patients with Major Depressive Disorder.

OBJECTIVES: Genetic polymorphisms may help for individualized drug dosing and improved therapeutics. CYP3A4 is responsible for the metabolism of more than 50% of the commonly used drugs and metabolizes typical antipsychotic medications and antidepressant drugs. The objective of the study was to assess the genotype and allele frequencies of CYP3A4 -392A>G in Turkish patients with major depressive disorder receiving any SSRIs and to compare these results with the frequencies of other ethnic groups. MATERIALS AND METHODS: Genotyping analyses of CYP3A4 -392A>G was conducted on 84 Turkish patients using the PCR-RFLP technique. RESULTS: The allele frequencies were found as 0.982 (A) and 0.018 (G) for CYP3A4 -392A>G. The genotype frequencies were determined as 0.976 (AA), 0.012 (AG), and 0.012 (GG). The genotype frequencies were consistent with the Hardy-Weinberg equilibrium. CONCLUSION: The genotype and allele frequencies of CYP3A4 -392A>G were determined to be low in Turkish patients with major depressive disorder receiving SSRIs. Furthermore, the results of the study were compared with those of other ethnic groups and they displayed pronounced differences among other ethnic groups, especially black subjects.

Clinical, genetic, and structural basis of apparent mineralocorticoid excess due to 11ß-hydroxysteroid dehydrogenase type 2 deficiency.

Mutations in 11ß-hydroxysteroid dehydrogenase type 2 gene (HSD11B2) cause an extraordinarily rare autosomal recessive disorder, apparent mineralocorticoid excess (AME). AME is a form of low renin hypertension that is potentially fatal if untreated. Mutations in the HSD11B2 gene result either in severe AME or a milder phenotype (type 2 AME). To date, ∼40 causative mutations have been identified. As part of the International Consortium for Rare Steroid Disorders, we have diagnosed and followed the largest single worldwide cohort of 36 AME patients. Here, we present the genotype and clinical phenotype of these patients, prominently from consanguineous marriages in the Middle East, who display profound hypertension and hypokalemic alkalosis. To correlate mutations with phenotypic severity, we constructed a computational model of the HSD11B2 protein. Having used a similar strategy for the in silico evaluation of 150 mutations of CYP21A2, the disease-causing gene in congenital adrenal hyperplasia, we now provide a full structural explanation for the clinical severity of AME resulting from each known HSD11B2 missense mutation. We find that mutations that allow the formation of an inactive dimer, alter substrate/coenzyme binding, or impair structural stability of HSD11B2 yield severe AME. In contrast, mutations that cause an indirect disruption of substrate binding or mildly alter intramolecular interactions result in type 2 AME. A simple in silico evaluation of novel missense mutations could help predict the often-diverse phenotypes of an extremely rare monogenic disorder.

The Bond Strength of Nanohybrid and Nanoceramic Composites to Feldspathic Porcelain.

BACKGROUND: Porcelain fracture is the most important problem in fixed prosthetic restorations. The replacement of fractured restoraions isn't often prefer by patients and dentists. Intraoral repair of fractured porcelain is a big alternative for patient and dentist. For this reason, dentists try to improve different surface treatments to increase the bond strength between porcelain and repair materials such as composite resins. AIMS: The aim of this study was to evaluate the shear bond strength (SBS) of nano-hybrid (Nh.com) and nano-ceramic composite resins (Nc.com) to this feldspathic porcelains (Vita and Ivoclar). SETTINGS AND DESIGN: 120 ceramic disc were fabricated from feldspathic porcelain. MATERIALS AND METHODS: The following surface treatment was applied on the ceramic surface: 1) Hydrofluoric acid+silane, 2) Air-abrasion+silane, 3) Air-abrasion=Control group. Nh.com and Nc.com was placed on the porcelain surface. Half of the specimens were stored in 37 ± 2oC distilled water and another half were subjected to thermocycling before SBS. The samples placed in an universal testing machine and applied shear force until seperation occured. STATISTICAL ANALYSIS USED: The data were analyzed by multi-way analysis of variance (ANOVA) and Duncan test (P <0.05). RESULTS: The results show that Ivoclar and Vita had almost equal fracture values. Nh.com showed high bond strength than Nc.com. In the Ivoclar porcelain, hydrofluoric acid etching had highest fracture values than other surface treatments, and in the vita porcelain air-abrasion had a little difference from hydrofluoric acid etching. CONCLUSIONS: Different surface treatments show different effect on SBS between feldspathic porcelain and composite resins.

Influence of CYP2B6 and CYP2C19 polymorphisms on sertraline metabolism in major depression patients.

BACKGROUND: Genetic polymorphisms in CYP2B6 and CYP2C19 may cause variability in the metabolism of sertraline, a widely used antidepressant in major depressive disorder treatment. OBJECTIVE: This study investigates the impact of CYP2B6*4 (785A > G), CYP2B6*9 (516G > T), CYP2B6*6 (516G > T + 685G > A) CYP2C19*2 (685G > A), CYP2C19*17 (-3402C > T) polymorphisms on plasma concentrations of sertraline and N-desmethyl sertraline in major depression patients treated with sertraline [n = 50]. SETTING: Participants were patients who admitted to an adult psychiatry outpatient unit at a university hospital. These were DSM-IV major depression diagnosed patients with a stable sertraline medication regimen [for at least one month]. METHODS: CYP2B6*4 (rs 2279343; 785A > G), CYP2B6*9 (516G > T; rs 3745274), CYP2B6*6 (516G > T + 685G > A) CYP2C19*2 (rs 4244285; 685G > A), CYP2C19*17 (rs 11188072; -3402C > T), polymorphisms were analyzed by polymerase chain reaction and restriction fragment length polymorphism. Plasma concentrations were measured by high-performance liquid chromatography in patients treated with SERT. MAIN OUTCOME MEASURE: The distribution of CYP2B6*4, *6, *9 and CYP2C19*2, *17 among patient group and the association between genotype and sertraline metabolism. RESULTS: Sertraline, N-desmethyl sertraline, N-desmethyl sertraline/sertraline and dose-adjusted plasma concentrations were statistically compared between individuals with wild-type and variant alleles both for CYP2B6 and CYP2C19 enzymes. The mean N-desmethyl sertraline/sertraline value, was significantly lower in all subgroups with *6 and *9 variant alleles (p < 0.05). Sertraline/C values were significantly higher (p < 0.05) and N-desmethyl sertraline/C values were lower in all subgroups with *6 and *9 variant alleles compared to wild-type subgroup. CONCLUSION: CYP2B6*6 and *9 variant alleles had a significant decreasing effect on sertraline metabolism in major depression patients which might result as variations in sertraline therapy.

Magical ideation associated social cognition in adolescents: signs of a negative facial affect recognition deficit.

BACKGROUND: Studies provide evidence for impaired social cognition in schizotypy and its association with negative symptoms. Cognitive features related to magical ideation - a component of the positive dimension of schizotypy - have been less investigated. We aimed to assess social cognitive functioning among adolescents with high magical ideation scores, mainly focusing on face and emotion recognition. METHODS: 22 subjects with magical ideation scale scores above the cut off level and 22 controls with lowest scores from among 250 students screened with this scale were included in the study. A face and emotion recognition n-back test, the empathy quotient, theory of mind tests and the Physical Anhedonia Scale were applied to both magical ideation and control groups. RESULTS: The magical ideation group performed significantly worse than controls on both face and emotion recognition tests. Emotion recognition performance was found to be affected by memory load, with sadness, among emotions, revealing a difference between the two groups. Empathy and theory of mind tests did not distinguish the magical ideation group from controls. CONCLUSION: Our findings provide evidence for a deficit in negative emotion recognition affected by memory load associated with magical ideation in adolescents.