The role of the mothers' sense of coherence in predicting dental caries risk in children.

BACKGROUND: Individuals with a stronger sense of coherence (SOC) often show healthier behaviors. As parents, especially mothers, are behavioral role models for their children, this study aimed to explore the role of the mothers' SOC in prediction of the risk of dental caries in a sample of children aged 11-12 years old. DESIGN: Cross-sectional study with 173 mother-child pairs enrolled by multi-stage sampling from four public schools in Torbat-e-Heydarieh, Iran. The data were obtained, using a demographic-health information sheet and the SOC-13 scale. Dental examinations of children were performed using the decay, missing and filled teeth index for primary (dmft) and permanent teeth (DMFT). Poisson regression analyses estimated the role of the mothers' SOC in predicting the relative risk (RR) of children's dental caries. RESULTS: Mean dmft and DMFT were 3.4 ± 3.1 and 2.7 ± 2.9 respectively (medium severity). After controlling for demographic and health variables in regression models, greater maternal SOC indicated a protective effect against dental caries in primary (RR: 0.96; 95% CI:0.96-0-97) and permanent teeth (RR: 0.96; 95% CI: 0.95-0.97) of their children. CONCLUSIONS: With greater maternal SOC, the risk of children's dental caries decreased. Whilst this relationship was not as strong as in previous studies in other countries, it can be a platform for further research and perhaps planning to identify children who are at a greater risk of dental caries before starting dental examinations in schools.

Intractable airsickness associated with COVID-19: A case report.

A 29-yr-old male Melicopter co-pilot with high flight hours in air transport missions of the patients with COVID-19 tested positive for his RT-PCR due to clinical suspicion. With the diagnosis of SARS-CoV-2, he was treated based on the national protocol and stayed in the home quarantine for two weeks. Having been released for flying, he faced nausea, vomiting, facial cold sweat and pallor, dizziness, and imbalance that eventually caused flying avoidance during the three first flights. He has never had a similar problem or any predisposing factors during his pilot's training and afterwards. All the probable reasons ruled out after a complete assessment. Following the diagnosis of moderate airsickness, he was abstained from flying and treated with different prevention and rehabilitation techniques. None of them had enough clinical efficacies, applying the United States Air Force Preventive Airsickness Protocol as the last choice. Despite the three separate consecutive therapeutic courses, no significant clinical improvement was observed, and could not return to fly, yet. That is the first reported case of intractable airsickness in a flight crew that may be associated with SARS-CoV-2 infection.

Un varón de 29 años de edad, copiloto de helicóptero médico, con gran número de horas de vuelo en misiones de transporte aéreo de los pacientes de COVID-19, dio positivo en las pruebas rápidas de PCR, debido a sospecha clínica. Diagnosticándose SARS-CoV-2, fue tratado sobre la base del protocolo nacional, permaneciendo en cuarentena domiciliaria durante dos semanas. Habiendo sido eximido de volar, padeció náuseas, vómitos, sudores fríos y palidez facial, mareos y falta de equilibrio, que le abstuvieron de volar durante las primeras tres semanas. No había tenido nunca un problema similar ni factores predisponentes durante su formación como piloto, ni después de esta. Tras un reconocimiento completo se descartaron todas las causas probables. Al diagnosticarse mareo moderado al volar, se le recomendó que se abstuviera de viajar en avión, tratándosele con diferentes técnicas de prevención y rehabilitación. Ninguna de ellas tuvo eficacia clínica suficiente, aplicándose el protocolo para la prevención de mareo al volar de las Fuerzas Aéreas de los Estados Unidos como última elección. A pesar de realizar los tres cursos terapéuticos separados consecutivos no se observó una mejora clínica significativa, y no pudo volver a volar. Se trata del primer caso reportado de mareo al volar irresoluble en una tripulación de vuelo, que puede estar asociado a la infección por SARS-CoV-2.

Effects of step-down weaning implementation time on growth performance and blood metabolites of dairy calves.

The current study evaluated the effects of step-down weaning implementation time on starter feed intake, growth performance, blood metabolites, and ruminal pH in dairy calves. A total of 48 Holstein dairy calves (24 male and 24 female; 3 ± 1 d old; 41.2 ± 1.8 kg of body weight) were assigned (n = 12 per treatment; 6 male and 6 female) to 4 experimental treatments in a completely randomized block design. All calves were fed 6 L/d of milk from d 3 to 10 of age, and the treatments consisted of the following: calves were offered 8 L/d of milk from d 11 to 28 of age and then 4 L/d from d 29 to 63 (Step-28; total milk offered = 326 L); calves were offered 8 L/d of milk from d 11 to 42 of age and then 4 L/d from d 43 to 63 (Step-42; total milk offered = 382 L); calves were offered 8 L/d of milk from d 11 to 56 of age and 4 L/d from d 57 to 63 (Step-56; total milk intake = 438 L); and calves were fed 8 L/d of milk from d 11 to 63 of age and abruptly weaned (control; total milk offered = 466 L). All calves were housed individually in pens and had ad libitum access to water and solid feed throughout the experiment. All calves were completely milk weaned on d 64, and their performance was measured until d 80 of age. During the experiment, the starter intake (kg/d and % of body weight) was greater in calves in the Step-28 group compared with those in the other groups. However, the total metabolizable energy intake was greater in the Step-56 calves compared with the other calves. Overall, the average daily gain (ADG), feed efficiency (ADG/dry matter intake), and ADG/total metabolizable energy intake were similar across the treatments. Circulating glucose, ß-hydroxybutyrate, blood urea nitrogen, albumin, total protein, alanine aminotransferase, and aspartate aminotransferase, as well as ruminal pH, were not affected by the treatments. The implementation of step-down weaning in early life (4-6 wk of age) could stimulate solid feed intake compared with weaning at a later age with no negative effect on performance.

A review of ultrasonic testing applications in additive manufacturing: Defect evaluation, material characterization, and process control.

Ultrasonic testing (UT) techniques are highly capable of detecting defects in engineering components. The present manuscript intends to review the ultrasonic testing techniques applied to additive manufacturing products; either in-situ or offline. While the in-situ applications of ultrasonic testing to additive manufacturing are more favorable, literature holds a few research works on this topic. On the other hand, most of the works reported on ultrasonic testing of additive manufacturing products deal with offline applications. In many of these works, samples with artificial defects are prepared and tested through ultrasonic testing techniques including laser ultrasonics, phased arrays, guided waves and immersion ultrasonic testing. These UT methods and their applications in damage detection of additive manufacturing products are discussed in detail. Moreover, the codes and standards which are currently being developed for ultrasonic testing of additive manufacturing products are introduced. The choice of UT methods in detecting defects and material characterization in additive manufacturing is found to be highly dependent on the manufacturing process and capabilities of UT techniques.

Identification of potential genomic regions for egg weight by a haplotype-based genome-wide association study using Bayesian methods.

1. Theoretically, haplotype blocks might be a more suitable alternative to SNP genotypes as they are usually better at capturing multi-allelic QTL effects, compared to individual SNP genotypes in genome-wide association studies. The objectives of this study were to identify genomic regions related to egg weight traits by Bayesian methods (BayesA, BayesB, and BayesN) that fit fixed-length haplotypes using GenSel software. 2. Genotypes at 294,705 SNPs, that were common on a 600K Affymetrix chip, were phased for an egg-laying hen population of 1,063 birds. Recorded traits included first egg weight (FEW) and average egg weight at 28, 36, 56, 66, 72 and 80 weeks of age. 2. Fitting 1Mb haplotypes from BayesB resulted in the highest proportion of genetic variance explained for the egg weight traits. Based on the trait, the genetic variance explained by each marker ranged from 27% to 76%. 3. Different haplotype windows associated with egg weight traits only explained a small percentage of the genetic variance. 4. The top one 1-Mb window on GGA1 explained approximately 4.05% of total genetic variance for the FEW. Candidate genes, including PRKAR2B, HMGA2, LEMD3, GRIP1, EHBP1, MAP3K7, and MYH were identified for egg weight traits. 5. Several genomic regions, potentially associated with egg weight traits, were identified, some of which overlapped with known genes and previously reported QTL regions for egg production traits.

Antibacterial effect of tramadol against Staphylococcus aureus and Pseudomonas aeruginosa: an in vivo study.

Some important adverse effects of local and regional anaesthesia including injection-site infection, epidural abscess and meningitis, are usually caused by bacteria such as Staphylococcus aureus and Pseudomonas aeruginosa. These infections can even cause the patient's death in severe cases. In the present study, the antimicrobial activity of tramadol was investigated on S. aureus and P. aeruginosa in BALB/c-sensitive mice. This experimental multigroup research study evaluated the effect of two different concentrations of injectable tramadol (12.5 and 25 mg/mL) on local infections caused by S. aureus and P. aeruginosa in BALB/c mice within 24 and 48 hours. The results showed that tramadol injection in the specified doses did not have a significant impact on the diameter of lesions caused by local infections due to these organisms. However, the diameter of inflammation resulting from local infection with P. aeruginosa had statistically increased in the two doses after 48 hours (p 0.019). Subcutaneous injection of tramadol reduced the growth of S. aureus through enhancing phagocytes and tissue inflammation; however, it did not help eliminate P. aeruginosa, and at a dose of 25 mg/mL it also increased the growth and spread of the bacteria. It seems that the observed difference was due to the different characteristics of these two bacteria.

Evaluation of GeneXpert MTB/RIF for determination of rifampicin resistance among new tuberculosis cases in west and northwest Iran.

Despite a Mycobacterium tuberculosis control programme and anti-tuberculosis drugs, drug-resistant tuberculosis (DR-TB) is one of the most serious public health issues worldwide. Rapid laboratory diagnosis of M. tuberculosis is needed for the diagnosis of multidrug-resistant (MDR) TB and to find the optimal treatment protocol. The purpose of this study was to detect resistance to rifampicin in new cases of TB using the GeneXpert MTB/RIF (M. tuberculosis/rifampicin) assay and the standard proportional method in west and northwest Iran. In this descriptive cross-sectional study, sputum samples were enrolled and screened for M. tuberculosis using Ziehl-Neelsen stain and mycobacterial culture. Samples from individuals with smear-positive TB were cultured on Lowenstein-Jensen medium; afterwards, the presence of resistance to rifampicin was examined by the GeneXpert MTB/RIF and standard proportional methods. A total of 400 new cases of suspected TB were collected, 162 (40.5%) of which were smear- and culture-positive for M. tuberculosis. The frequencies of rifampicin resistance in new smear-positive TB cases were 3.1% and 4.3% for GeneXpert and standard proportional method, respectively. Sensitivity and specificity of GeneXpert were 71% and 100%, respectively, compared with the proportional method. GeneXpert can be a quick and helpful method for the diagnosis of rifampicin-resistant TB in regions with high rates of DR-TB or MDR-TB. GeneXpert MTB-RIF assay must be used as an early diagnostic method whose results must be confirmed by the standard proportional method. The GeneXpert and proportional methods complement but do not replace each other.

Dental anomalies: prevalence and associations between them in a large sample of non-orthodontic subjects, a cross-sectional study.

BACKGROUND: To analyze the prevalence and associations between dental anomalies detectable on panoramic radiographs in a sample of non-orthodontic growing subjects. METHODS: For this cross-sectional study, digital panoramic radiographs of 5005 subjects were initially screened from a single radiographic center in Rome. Inclusion criteria were: subjects who were aged 8-12 years, Caucasian, and had good diagnostic quality radiographs. Syndromic subjects, those with craniofacial malformation, or orthodontic patients were excluded and this led to a sample of 4706 subjects [mean (SD) age = 9.6 (1.2) years, 2366 males and 2340 females]. Sample was subsequently divided into four subgroups (8, 9, 10, and 11-12 year-old groups). Two operators examined panoramic radiographs to observe the presence of common dental anomalies. The prevalence and associations between dental anomalies were also investigated. RESULTS: The overall prevalence of dental anomalies was 20.9%. Approximately, 17.9% showed only one anomaly, 2.7% two anomalies, while only 0.3% had more than two anomalies. The most frequent anomalies were the displacement of maxillary canine (7.5%), hypodontia (7.1%), impacted teeth (3.9%), tooth ankylosis (2.8%), and tooth transposition (1.4%). The lower right second premolar was the most frequent missing teeth; 3.7% had only one tooth agenesis, and 0.08% had six or more missing tooth (Oligodontia). Mesiodens was the most common type of supernumerary tooth (0.66%). Two subjects had taurodontic tooth (0.04%). Tooth transpositions and displacement of maxillary canine were seen in 1.4 and 7.5%, retrospectively (approximately 69 and 58% were in the 8 and 9 year-old groups, retrospectively). Significant associations were detected between the different dental anomalies (P < .05). CONCLUSIONS: The results of our study revealed significant associations among different dental anomalies and provide further evidences to support common etiological factors.

Clonal evolution multi-drug resistant Acinetobacter baumannii by pulsed-field gel electrophoresis.

BACKGROUND: Acinetobacter baumannii is usually multi-drug resistant (MDR), including third generation cephalosporins, amino glycosides and fluoroquinolone. Resistance to these antibiotics is mediated by multiple factors such as: lactamases, efflux pumps and other mechanisms of resistance. Pulsed-field gel electrophoresis (PFGE) was then used to investigate the genetic relationships among the MDR isolates. AIM: The aim of this study was to determine MDR isolates and the existence of OXAs genes among MDR isolates of A. baumannii collected from Kermanshah hospitals in west of Iran. MATERIALS AND METHODS: Forty-two MDR A. baumannii were collected from patients at Kermanshah hospitals. The isolates were identified by biochemical tests and API 20NE kit. The susceptibility to different antibiotics by disk diffusion method was determined. Polymerase chain reaction (PCR) was performed for detection of blaOXA-23-like , blaOXA-24-like , blaOXA-51-like and blaOXA-58-like betalactamase genes in isolates and clonal relatedness was done by PFGE (with the restriction enzyme ApaI) and patterns analyzed by Bionumeric software. RESULTS: This study showed high resistant to ciprofloxacin, piperacillin, ceftazidime and also resistant to other anti-microbial agents and more spread blaOXA-23-like gene (93%) in MDR isolate. The PFGE method obtained six clones: A (10), B (9), C (5), D (4), E (11) and F (3) that clone E was outbreak and dominant in different wards of hospitals studied. CONCLUSION: An isolate from the emergency ward of these hospitals had indistinguishable isolates PFGE profile and similar resistance profile to isolates from intensive care unit (ICU), suggesting likely transmission from ICU to emergency via patient or hospital staff contact.

One-year clinical evaluation of a Glass Carbomer fissure sealant, a preliminary study.

Glass Carbomer is a new generation of restorative material developed from glass-ionomer cements with possibility of gradual mineralization into fluorapatite. The aim of this clinical trial was to investigate the retention of Glass Carbomer fissure sealant after 12 months, in comparison to a commonly used conventional resin-based sealant. Forty-eight teeth in 24 patients [mean (SD) = 8 (2.3) years] with well-delineated fissure morphology were randomly divided into two equal groups and sealed with Bis-GMA resin-based Helioseal F (group A, Ivoclar Vivadent, Liechtenstein) and Glass Carbomer (group B, Glass Carbomer Sealant, Glass Carbomer Products, Leiden, Netherlands) using the split mouth design. Materials were placed and set according to the manufacturer's instructions using a polymerization unit Bluephase 16i (Vivadent, Liechtenstein). Complete sealant retentions in both groups were 100% and 75% after 6 and 12 months of clinical service, respectively. There were there were no secondary caries lesions in both groups after 6 months; two new carious lesions were detected in both groups after 12 months. The Mann-Whitney U test revealed no significant difference between the two groups at both evaluations points (P > 0.05). Glass Carbomer material showed a similar retention rate when compared with a resin-based sealant. Future studies are required to examine the long-term performance of Glass Carbomer sealants.

Is buccolingual angulation of maxillary anterior implants associated with the crestal labial soft tissue thickness?

We aimed to examine the relationship between crestal labial soft tissue thickness (CLSTT, measured with a digital calliper at the crestal level of casts) and implant buccolingual angulation (IBLA). The records of 22 females and 10 males treated with two bone-level implants (3.3-4.6mm) between the maxillary canines were evaluated. IBLA was recorded as cingulum, incisal, or labial based on the screw access hole position on provisional restorations. Postoperative implant labial bone thickness (ILBT) at the crestal (2mm from crest) and mid-implant levels were measured on sectional cone beam computed tomography scans. The mean (SD) ridge width at the crestal level was 6.81 (0.98) mm. Mean (SD) CLSTT for implants with cingulum, incisal, and labial angulations were 2.98 (0.84), 2.24 (0.51), and 1.71 (0.72) mm, respectively. Significant differences were detected between CLSTT of implants with cingulum and incisal, as well as cingulum and labial angulations (P<0.01). Of implants with cingulum, incisal, and labial angulations, 3.4%, 20%, and 53.3%, respectively, had a CLSTT<2mm. Overall, 74.2% of CLSTT variance could be predicted by IBLA and ILBT at the crestal and mid-implant levels. A significant association between CLSTT and IBLA was noted when ILBT (crestal level) was <2mm (P<0.01). Implants with labial angulations carry a higher risk of soft tissue complications when the crestal implant labial bone thickness is <2mm.

The effect of pore-formers and plasticizers on the release kinetic of diltiazem hydrochloride from the controlled porosity osmotic pumps.

BACKGROUND: The aim of this study was to design a controlled porosity osmotic pump (CPOP) tablet of diltiazem hydrochloride (DLTZ) to deliver the drug according to the zero order kinetic model over 24 h. METHOD: CPOPS were prepared by incorporating DLTZ in the tablet core followed by coating with cellulose acetate solution containing various types of pore-formers (PVP, PEG 2000, PEG 6000 and PEG 20000) and plasticizers (glycerol, castor oil and diethylphthalate). In vitro release study was conducted for the prepared formulations and the dissolution profiles were compared throughout four parameters, namely, D24 h (cumulative release in 24 h), tL (lag time), RSQzero (squared correlation coefficient of zero order kinetic) and MPDzero (mean percent deviation from zero order equation). RESULTS: Scanning electron microscopy showed formation of the pores in the semi-permeable membrane after coming in contact with dissolution medium. All formulations released more than 76% of contained drug during 24 h. CONCLUSION: Drug release rate and lag time were found to be directly proportional to the type and concentration of pore-formers as well as hydrophilicity of plasticizers. Our findings indicated that by optimizing formulation variables, CPOP tablets obeying zero order drug release kinetic could be obtained.

Dioxins and furans releases in Iranian mineral industries.

In this project, emissions of Poly-Chlorinated Dibenzo-p-Dioxins and Dibenzo-Furans (PCDD/Fs) were investigated and estimated for selected Iranian mining and ore processing industries, such as integrated iron & steel plant, primary production of aluminium and copper metal, and the production of cement. As a first step of this study the annual emission of PCDD/Fs was estimated at 120gTEQannum(-1) on the base of the UNEP standardised Toolkit for identification and quantification of dioxin and furan releases. Steel and cement were identified as major emission sources and earmarked for further scrutiny. For that reason, filter dust arising in these plants was sampled and analysed, as well as all raw materials employed. After extraction and clean-up according to standard methods, the resulting liquid samples were analysed and quantified by HRGC-HRMS. Complementary analyses using methods such as XRF, TGA/DTA were performed and the emission results statistically evaluated, in order to put PCDD/F emissions in perspective. It is concluded that the dioxins load of cement dust is unusually low, following the low carbon in raw materials, the use of natural gas as a fuel and the absence of waste incineration. Also the production of iron by direct reduction of ore is a low dioxins process; dioxin loads in dust are as usual - correlated with the presence of catalytic metals. Loss on ignition and chlorine are anti-correlated with the main earth elements and with sulphur oxides.

Aflatoxin in raw walnut kernels marketed in Tehran, Iran.

The occurrence of aflatoxin in 35 samples of raw walnuts, which were randomly collected from Iranian supermarkets in Tehran, was examined. Analysis of aflatoxin was performed by solvent extraction and immunoaffinity clean-up followed by determination using high-performance liquid chromatography with fluorescence detection. Limits of detection (LOD) for the aflatoxins were 0.03-0.25 ng g⁻¹. Limits of quantification (LOQ) were 0.12-0.80 ng g⁻¹. Total aflatoxin concentrations in the samples ranged from 0 to 112.8 ng g⁻¹. About 74.3% of the samples were contaminated with aflatoxins, of which 20.0% exceeded the maximum tolerable limit of 15 ng g⁻¹ set by Codex.

Outcomes of stenting with overlapping drug-eluting stents versus overlapping drug-eluting and bare-metal stents for the treatment of diffuse coronary lesions.

INTRODUCTION: we investigated the outcomes of stenting with overlapping drug-eluting stents (DES) versus overlapping stenting with a combination of drug-eluting and bare metal stents (BMS) in very long coronary lesions (≥ 25 mm). METHODS AND RESULTS: fifty-two patients treated with either overlapping DES-DES (n = 22) or DES-BMS (n = 30) were selected from a registry of 588 patients with very long coronary lesions. Patients with acute myocardial infarction (MI) within the preceding 48 hours were excluded. The DES-DES combination was more frequently used for longer lesions compared with the DES-BMS group (47.95 ± 9.25 vs 39.98 ± 9.15 mm, p = 0.003). Left anterior descending artery lesions were also more frequently treated with the DES-DES combination (95.5 vs 66.7%, p = 0.02). In four patients in the DES-BMS group, overlapping stents were used for the coverage of dissections. Peri-procedural non-Q-wave MI occurred in one patient in the DES-BMS group. On follow up, only one case of non-fatal MI occurred in a patient with overlapping DES-DES. CONCLUSION: overlapping a BMS in the proximal part of a long DES instead of exclusive deployment of two or more overlapped DES seems to be a safe and feasible therapeutic strategy in our practice.

Positive exercise tolerance test (ETT) on asymptomatic Iranian cases aged over 60 years.

AIM: The purpose of this study was to determine the prognostic importance of positive exercise treadmill test (ETT) in predicting coronary artery disease (CAD) among asymptomatic population based on coronary angiographic findings. METHODS: The comparative study was conducted on a sample of over 60-year-old asymptomatic and symptomatic patients referred to our clinics for screening and clinical reasons between September 2006 and September 2007. All subjects with a positive ETT provided information about their cardiovascular risk factors through a validated questionnaire. The relationship between ETT performance and the CAD risk factors with coronary angiography were studied and compared between the two groups. RESULTS: Seven hundred thirty one symptomatic and 160 asymptomatic individuals were enrolled in the study. In the symptomatic group, gender, blood pressure and diabetes were significantly related with the angiographic findings, while blood pressure failed to show such a relation in the asymptomatic group. CONCLUSION: There is an association between positive ETT and the presence of CAD among asymptomatic elderly men but also women with diabetes or high blood pressure.

The relationship between aging and oral health inequalities assessed by the DMFT index.

AIM: A cross-sectional study to determine the caries experience characteristics and their relationship with aging. MATERIALS AND METHODS: Using stratified sampling method, 748 subjects divided into 3 age groups of 11-14, 14-17 and 17-20 year-olds (355 females and 393 males, aged 15.11 ± 2.23 years) were examined in urban area of Isfahan (Iran). The DMFT scores (DT, MT, FT) were recorded. The Student t-test was used to assess any differences in the mean DMFT score between genders. Simple (DMFT >0), severe caries experience (DMFT >8), severe form of filling (FT>3), and decay (DT>6) were calculated. Chi-square tests were performed to assess any relationship between gender and DMFT variables. Binary logistic regression was used to estimate the predictive value of gender and age groups for the DMFT categories dichotomized into presence or absence of DMFT-related variable. Scatter plots and Spearman rank correlation coefficients were used to explore the relationships between the DMFT (DT, MT, FT) and participant's age. RESULTS: The mean DMFT values for the sample, 11-14, 14-17 and 17-20 year-olds were 4.94, 3.03, 5 and 6.66, respectively. Caries prevalence (DMFT >0) and active caries prevalence (DT >0) were 88.8% and 81.8%, respectively. Prevalence of active caries (DT) did not vary significantly between genders; however, prevalence of fillings (FT) was higher in females (OR 1.96, 95% CI, 1.45-2.67). The odds of experiencing caries (DMFT, DT, FT) increased with increase in participant's age. Prevalence of subjects with DT>6 was higher in males than in females (OR 1.50, 95% CI, 1.04-2.01). Prevalence of subjects with FT>3 was higher in females than in males (OR 1.74, 95% CI, 1.10-2.73). Significant positive correlations existed between the participant's age and DMFT (rho 0.40), DT (rho 0.34) and FT scores (rho 0.194), respectively. CONCLUSION: Caries experience was highly prevalent in our sample. With increase in age, there was an upward trend in caries prevalence and mean DMFT.

Orthodontic treatment needs in an urban Iranian population, an epidemiological study of 11-14 year old children.

OBJECTIVES: A preliminary study to investigate the orthodontic treatment need and its gender distribution in urban Iranian schoolchildren. STUDY DESIGN: A cross-sectional study was carried out at the school premises. SUBJECTS AND METHODS: For this survey, 502 subjects attending 6 different schools in the city of Isfahan, Iran (253 females and 249 males, aged 11-14 years) were randomly selected and examined, including those who were wearing an orthodontic appliance at the time of the survey (1 female and 5 males). IOTN (DHC and AC) scores were recorded for those who were not undergoing orthodontic treatment. One examiner, who had been formally calibrated in the use of occlusal indices, screened all schoolchildren. IOTN scores was calculated from direct examination. Gender dimorphism was evaluated by the Chi-square test (AC and DHC components of IOTN index). The prevalence of most severe occlusal traits in those who scored DHC 4 and 5 was calculated. RESULTS: At the time of the survey, 1.1% of subjects were wearing an orthodontic appliance, 36.1% had definite need (DHC 4 or 5) for orthodontic treatment, 20.2% borderline need (DHC 3) and 43.8% showed slight or no need for treatment (DHC 1 or 2). Reviewing the AC scores, 17.9% of the studied subjects showed definite need (AC 8-10) for orthodontic treatment, 36.1% borderline need (AC 5-7) and 46% showed slight or no need for treatment (AC 1-4). The prevalence of the four most severe occlusal traits in those with definite orthodontic treatment need were: severe maxillary crowding (43.6%), increased overbite (39.1%), increased overjet (35.8%) and severe mandibular crowding (27.4%). No gender differences were found for AC (P>0.05) and DHC (P>0.05) of IOTN index. CONCLUSION: Approximately one-third of Iranian school children were in need of orthodontic treatment, as determined by the index of orthodontic treatment need.

In vivo study of metal content of oral mucosa cells in patients with and without fixed orthodontic appliances.

OBJECTIVE: To compare the concentration of nickel, chromium and cobalt in oral mucosa cells of patients with and without fixed orthodontic appliances. MATERIALS AND METHODS: A total of 60 patients were included in this study. The control group consisted of 30 patients without any type of fixed orthodontic appliances or metal restoration in the mouth (20 females and 10 males from 16 to 20 years with a mean age of 18 years). The test group consisted of 30 patients who had fixed orthodontic appliance in their upper and lower arches (20 females and 10 male from 16 to 20 years with a mean age of 18.2 years). The metal content determinations were carried out using atomic absorption spectrophotometry with a graphite furnace. RESULTS: According to spectrophotometric analysis, no significant differences in chromium (p = 0.09) and cobalt (p = 0.10) content of oral mucosa cells were found between the test and control samples. The nickel content in mucosa samples was significantly higher (p = 0.003) in orthodontic patients compared with the controls. The mean levels of nickel in control and orthodontic patient group were 12.26 and 21.74 ng / ml, respectively. CONCLUSION: Our findings indicate that there was no difference in the concentration of chromium and cobalt in oral mucosa cells of patients with or without fixed appliances. However, a significantly higher concentration of nickel can be found in oral mucosa cells of patients wearing fixed orthodontic appliances. Continued follow-up is needed to determine the long-term significance of nickel release.