Orofacial clefts and risk factors in Tehran, Iran: a case control study

Non-syndromic cleft lip with or without cleft palate [CL/P] or cleft palate only [CPO] are orofacial clefts with multifactorial etiology. These include environmental factors and heterogeneous genetic background. Therefore, studies on different and homogenous populations can be useful in detecting related factors. The aim of the present study was to evaluate the risk factors in patients with non-syndromic cleft in Tehran, Iran. Data from 300 patients and 300 controls were collected between 2005 and 2010. Binary logistic regression analyses were used to calculate relative risk by odds ratio [OR] and%95 confidence interval. Low maternal age [OR=1.06, 95% Cl, 1.011-1.113], low socioeconomic status [OR=0.23, 95% Cl, 0.007-0.074], maternal systemic disease [OR=0.364; 95% Cl, 0.152-0.873] and passive smoking [OR=0.613, 95% Cl, 0.430-0.874] increased the risk for CL/P and CPO. There was a significant difference in iron and folic acid use during pregnancy when the case and control groups were compared. In assessing for orofacial cleft risk, we should consider lack of folic acid supplementation use, maternal age and systemic diseases and passive smoking as risk factors

[ effect of different surface cleaning methods on shear bond strength of porcelain to immediately sealed dentin]

Statement of Problem: There is a probability of interaction between impression materials especially Polyether with the external surface of the adhesive layer of the immediately sealed dentin in the presence of oxygen inhibited layer

Purpose: The aim of the present study was to evaluate the effect of three different surface cleaning methods on the shear bond strength of porcelain to the immediately sealed dentin

Methods and Material: In this in-vitro study, the facial surfaces of 60 extracted premolars were immediately sealed, using single-bond adhesive. Then, the immediately sealed dentin surfaces were buried in the polyether impression material while setting. After the impression materials were removed, the samples were randomly divided into 4 groups. In group 1, porcelain samples were bonded to the teeth surfaces using resin cement without any surface cleaning. In groups 2, 3 and 4, surface cleaning using acid etche, air abrasion and pumice with rubber cup prophylaxis were applied respectively for each group before bonding the porcelain samples. Shear bond strength test was performed at the strain rate of 0.5 mm/min. The data were analyzed using One-way ANOVA and Tukey posthoc tests

Results: There were significant differences between the shear bond strength of the control group and the three surface cleaning method groups [p <0.001]. The mean of the shear bond strength in the acid etch group was greater than that of the two other experimental groups; however, there were no significant differences between the three surface cleaning methods [p = 0.5]

Conclusion: Surface cleaning of immediately sealed dentin using acid etche, air abrasion and prophylaxis, after impression with polyether, significantly improves the strength of the bond

life time prevalence of childhood seizure

Seizure is the most common pediatric neurologic disorder. Epidemiological studies of childhood epilepsy are of importance to compare incidence and prevalence rates, age distribution, inheritance, seizure types, epilepsy syndromes and treatment strategies. Since there is little information about prevalence of childhood seizure in Iran, this study was aimed to determine the life time prevalence of childhood seizure and some of its determining factors in Tehran, Iran. In this cross sectional study, 2500 male and female students, aged 12 years or younger, studying in fifth grade of primary schools in district one of Ministry of Education were assessed by filling a preliminary questionnaire. Those who were categorized by the author as having a history of any form of seizure were assessed by a second questionnaire. The clinical form of seizure, the presumptive cause, positive family history and use of anti-convulsant drugs were recorded. The life time prevalence of seizure was 32/1000 population which was more prevalent in boys. Generalized seizure was the most common clinical form. Approximately 60% of cases reported febrile convulsion as the presumptive cause stated by the physician. Positive family history was reported in 29.6% of cases. Anti epileptic drugs were taken by 54% of students with a positive history of seizure. The results of this study show that the life time prevalence of seizure is relatively high in Iranian community, although the other factors were in concordance with other communities

[ effect of three different curing methods on the microleakage of Clv posterior composite restorations]

Light-cured composites have become almost universal in modern clinical dentistry. Unfortunately, these materials have demonstrated critical limitations such as postoperative sensitivity and polymerization shrinkage. The aim of this study was to evaluate the effects of three curing modes on the microleakage of class V composite restorations. In this experimental in vitro study, class V cavities were prepared on the buccal surfaces of 90 extracted human molar and premolar teeth and were randomly divided into 3 groups. All teeth were etched followed by bonding and composite filling. Three different methods were used for curing: conventional, 750 mw/cm2/40s; pulse delay, 400 mw/cm2/5s-5 minutes delay-750 mw/cm2/35s; and soft start, beginning at 150 mw/cm2 and increasing to 750 mw/cm2 during 15 seconds and remaining for another 35 seconds. After polishing, the specimens were stored in a 37°C incubator, thermocycled [500 cycles] and immersed in basic%0.5 fushin. Longitudinal buccolingual sections of all teeth were scored for marginal dye penetration under a stereomicroscope. Kruskal-Wallis test was used for statistical analysis. Leakage was observed in all groups but no significant difference was found in the microleakage scores among the three light-curing techniques, used in this investigation. These findings suggest that the 3 studied light-curing methods may have no effect on the microleakage of class V posterior composite restorations

effect of horizontal pin on fracture resistance of composite restored endodontcally treated teeth

Restoration of endodontically treated teeth by a simple method, with low cost in a short time is one of the major problems in dentistry. The purpose of this study was to evaluate the effect of horizontal pins in fracture resistance of endodontically treated maxillary premolars restored with composite. In this study, 48 sound, closed apex, maxillary human premolars, without crack, extracted for orthodontic reasons, were randomly divided into 3 groups of 16 as follows; Group 1: intact [unprepared] teeth. Group 2; composite restoration without horizontal pin. Group 3: composite restoration with 2 horizontal pins in buccal cusp. In groups 2,3 after preparation of the standard access cavity and endodontic treatment, the palatal cusp was reduced to 1.5 mm coronal to the CEJ, leaving the remaining buccal cusp 3mm in buccolingual thickness at the height of contour. After thermocycling, each tooth was loaded in compression until fracture occured. Data were analyzed with one-way ANOVA and Tukey test. The pattern of fracture was analyzed by Chi-Square test. The mean fracture resistance in groups 1-3 were 689.59 +/- 179, 632.86 +/- 119 and 533.49 +/- 168 [in N] respectively. The differences between group 1 and group 3 were statistically significant [p<0.05]. Among patterns of fracture, the maximum number of favourable fractures occured in group 1 and the minimum number was in group 3. 1] Composite restoration with dentin bonding agents in endodontically treated maxillary premolars increased resistance to fracture. 2] Horizontal pins caused statistically significant reduction in fracture resistance of teeth. 3] The use of horizontal pins did not result in favorable fracture pattern

Effect of early bathing on temperature of normal newborn infants

Nowadays there is a strong tendency for early bathing of healthy newborns but little is known about the thermal stability of newborns in response to early bathing. The aim of this study was to compare the thermal effect of bathing on healthy newborn within 1-2 h of life versus 4-6 h after birth. In this randomized comparative study 100 healthy newborns in a newborn nursery of a charity hospital in Tehran were studied. The inclusion criteria were: healthy term [>/= 37 wk] newborn over 2500 grams with rectal temperature > 36.5 °C, apgar score > 7 in 1 and 5 min after birth and lack of manifestations of any diseases like sepsis or respiratory distress syndrome .The exclusion criteria were the history of recent fever, leukocytosis, urinary tract infections and using medicines in their mothers. In the experimental group, 50 newborns were bathed within the first 1-2 h of birth; those in control group were bathed at the 4-6 h of age. Rectal temperatures were measured in four different times: before bathing and immediately as well as 30 and 60 min after bathing. Rectal temperatures as measured at four different times did not differ significantly between infants bathed within 1-2 h of birth and those bathed 4-6 h after birth .There were no significant differences between the groups in types of gender, birth weight, gestational age, parity, delivery route, interval time between rupture of membranes and delivery, apgar scores at 1 and 5 min of age. Healthy full term newborns with rectal temperature > 36.5 °C can be bathed within 1-2 h of birth without any risk of hypothermia

effect of mechanical surface conditioning methods on the shear bond strength of repaired composites

Considering the cost and quantity of tooth loss in the process of cavity preparation, repairing composite restorations instead of replacing them would be much more efficient. The aim of this study was to evaluate and compare the effectiveness of different mechanical surface treatment methods on the shear bond strength [585] between old and new composites. In this experimental in vitro study, 80 cylindrical specimens were fabricated from Tetric Ceram Composite [A[1], vivadent] and were preserved in 37°C distilled water. They were divided into 4 groups according to the surface treatment method: control [no treatment], roughening by a diamond bur, polishing with Sof-Lex disks and air-abrasion. All specimens were thermocycled [0.5-55°C, 500 cycles] prior to testing for SBS. An Instron Universal Testing Machine [5mm/mm Cross head imm] was used to evaluate the SBS of the specimens. Data were analysed by one-way ANOVA and Duncan tests. The highest to lowest shear bond strengths were seen in the Sof-Lex disk, air abrasion, diamond bur and control groups, respectively. A significant difference was observed between all three experimental groups [air abrasion diamond bur, Sof-Lex-disk] and the control group. There were no significant differences between the air abrasion and diamond bur groups, but the other groups revealed a significant difference when compared as pairs. Adequate wetting and induction of a microretentive surface, may explain the high SBS observed in the Sof-Lex group. The results of this study emphasize the importance of mechacinal surface conditioning prior to composite restoration repair