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21.

Introduction

The purpose of this study was to evaluate the fracture strength of roots instrumented with the Self-Adjusting File (SAF; ReDent-Nova, Ra’anana, Israel) and the ProTaper system (Dentsply Maillefer, Ballaigues, Switzerland) and filled with the cold lateral compaction technique.

Methods

In total, 50 mandibular premolar teeth were sectioned at or below the cementoenamel junction to obtain roots 13 mm in length. The roots were balanced with respect to buccolingual-mesiodistal diameters and weight. They were distributed into 4 experimental groups and 1 control group (n = 10): no instrumentation (control group), instrumentation with ProTaper rotary files but no filling (PT), instrumentation with ProTaper rotary files and filling with cold lateral compaction (PT filling), instrumentation with SAF but no filling (SAF), and instrumentation with SAF and filling with cold lateral compaction (SAF filling). AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) was used along with gutta-percha points. One week later, a vertical load was applied to the specimen’s canal until fracture occurred. Data were statistically analyzed using 1-way analysis of variance (P = .05).

Results

The mean fracture load was 244 ± 51 N for the control group, 226 ± 21 N for the PT, 242 ± 45 N for PT filling, 233 ± 14 N for the SAF, and 271 ± 44 N for SAF filling. However, the differences were not statistically significant (P > .05).

Conclusions

Instrumentation with the SAF or the ProTaper rotary system did not change the fracture strength of standardized roots with respect to cross-sectional diameter and weight.  相似文献   
22.

Introduction

We compared the effects of 6 different rotary systems on transportation, canal curvature, centering ratio, surface area, and volumetric changes of curved mesial root canals of mandibular molar via cone-beam computed tomographic (CBCT) imaging.

Methods

Mesiobuccal root canals of 120 mandibular first molars with an angle of curvature ranging from 20°–40° were divided into 6 groups of 20 canals. Based on CBCT images taken before instrumentation, the groups were balanced with respect to the angle and radius of canal curvature. Root canals were shaped with the following systems with an apical size of 25: OneShape (OS) (MicroMega, Besancon, France), ProTaper Universal (PU) F2 (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper Next X2 (Dentsply Maillefer), Reciproc (R) R25 (VDW, Munich, Germany), Twisted File Adaptive (TFA) SM2 (SybronEndo, Orange, CA), and WaveOne primary (Dentsply Tulsa Dental Specialties, Tulsa, OK). After root canal preparation, changes were assessed with CBCT imaging. The significance level was set at P = .05.

Results

The R system removed a significantly higher amount of dentin than the OS, PU, and TFA systems (P < .05). There was no significant difference among the 6 groups in transportation, canal curvature, changes of surface area, and centering ratio after instrumentation.

Conclusions

The 6 different file systems straightened root canal curvature similarly and produced similar canal transportation in the preparation of mesial canals of mandibular molars. R instrumentation exhibited superior performance compared with the OS, TFA, and PU systems with respect to volumetric change.  相似文献   
23.
New files (ProTaper Next/HyFlex/OneShape) are made from novel nickel‐titanium (NiTi) alloys/treatments. The purpose of this study was to compare the cyclic fatigue resistance of these new instruments with that of Revo‐S instruments. Four groups of 20 NiTi endodontic instruments were tested in steel canals with a 3 mm radius and a 60° angle of curvature. The cyclic fatigue of the following NiTi instruments with a tip size 25 and 0.06 taper that were manufactured with different alloys was tested: ProTaper Next X2 (M‐Wire), OneShape (conventional NiTi), Revo‐S Shaping Universal (conventional NiTi) and HyFlex 25/0.6 (controlled memory NiTi wire). A one‐way anova and post‐hoc Tukey's test (α = 0.05) revealed that the HyFlex files had the highest fatigue resistance and the Revo‐S had the least fatigue resistance among the groups (P < 0.001).  相似文献   
24.
25.

Background/Aim

The aim of the present study was to investigate the prevalence of obesity-related dermatoses in obese children, and the association between these dermatoses and insulin resistance as well as skin color.

Methods

Obese, overweight, and normal weight children according to body mass index who were followed up and treated in the outpatient clinics were included in the study. Dermatological examinations of the participants were performed, and fasting insulin and glucose levels were checked.

Results

The obese and overweight children were evaluated as the patient group (70 girls, 41 boys, mean age: 12.37 ± 3.14 years). One hundred one healthy children with normal weight were determined as the control group (59 girls, 42 boys, mean age: 12.15 ± 2.43). The first five common dermatoses in the patient group when compared with the control group were keratosis pilaris (KP), striae distensae, hyperhidrosis, acanthosis nigricans (AN), and plantar hyperkeratosis. The first five dermatoses which were positively correlated with formation and insulin resistance were KP, striae distensae, AN, hyperhidrosis, and plantar hyperkeratosis. According to the Fitzpatrick skin scale, we found that the darker the skin color, the higher the probability of AN and KP (OR, 0.298; 95% CI, 0.106–0.834, p = 0.021; OR, 0.306; 95% CI, 0.117–0.796, p = 0.015, respectively).

Conclusion

Some dermatoses associated with obesity and insulin resistance were not found in obese children, or there was no significant association. These results indicate that many skin morbidities may be prevented by preventing and treating obesity and insulin resistance in the early period.  相似文献   
26.
27.
[Purpose] The aim of this retrospective study was to determine the associations between clinical, physical, and neurophysiological outcomes and self-reported symptoms and functions of patients after surgical carpal tunnel release. [Subjects and Methods] Among 261 patients who had undergone open surgical carpal tunnel release within the last three years, 83 (mean age 50.27 ± 11.13 years) participated in this study. Their socio-demographics and comorbidities were recorded. The intensity of pain, paresthesia, and fatigue symptoms in the hand were assessed by means of a Visual Analogue Scale, the Semmes-Weinstein Monofilaments test of light touch pressure sensation, and Jamar dynamometry for measurement of grip and pinch strengths. The Boston Carpal Tunnel Questionnaire evaluated the severity of symptoms and hand functional status, and the variables were analyzed by multivariate linear regression. [Results] The severity of the symptoms and functional status of release surgery patients was associated with diabetes mellitus, migraine, night pain, paresthesia and fatigue symptoms, impaired light touch pressure, and lack of medical treatment. [Conclusion] Appropriate post-surgery treatment programs for these factors should be taken into consideration to help patients obtain optimal functionality and health in their daily lives.Key words: Carpal tunnel syndrome, Patient outcome assessment, Surgical therapy  相似文献   
28.

Objective

The aim of this study was to determine the cardiometabolic risk factors in different polycystic ovary syndrome (PCOS) phenotypes.

Subjects and Methods

This cross-sectional study was performed between 2010 and 2011. Eighty-nine patients with PCOS and 25 age- and weight-matched healthy controls were included in the study. Patients were grouped using the Rotterdam 2003 criteria as: group 1, oligomenorrhea and/or anovulation (ANOV) and hyperandrogenemia (HA) and/or hyperandrogenism (n = 23); group 2, ANOV and polycystic ovaries (PCO; n = 22); group 3, HA and PCO (n = 22); group 4, ANOV, HA and PCO (n = 22); group 5, controls (n = 25). Laboratory blood tests for diagnosis and cardiometabolic risk assessments were performed. Insulin resistance (IR) was calculated in all patients with the homeostasis model assessment of IR (HOMA-IR) formula. An euglycemic hyperinsulinemic clamp test was performed on 5 randomly selected cases in each subgroup, making 25 cases in total, and indicated as the ‘M'' value (mg/kg/min), which is the total body glucose disposal rate.

Results

The mean BMl values of the groups were: group 1, 26.1 ± 5.3; group 2, 27.9 ± 5.2; group 3, 24.3 ± 4.2; group 4, 27.9 ± 7.5; group 5, 24.7 ± 5.2 (p > 0.05). There were no differences in the lipid profile, plasma glucose, HOMA-IR, insulin and M values between the groups (p > 0.05). Phenotypes with oligomenorrhea/anovulation (groups 1, 2 and 4) were more obese than group 3 (p = 0.039).

Conclusions

The cardiometabolic risk profile was similar among the PCOS subgroups. This finding could be attributed to the mean BMl values, which, being below 30, were not within the obesity range. Obesity appeared to be an important determinant of high cardiovascular risk in PCOS.Key Words: Polycystic ovary syndrome, Cardiovascular system, Obesity  相似文献   
29.
In two large Turkish consanguineous families, a locus for autosomal recessive nonsyndromic hearing loss (ARNSHL) was mapped to chromosome 6p21.3 by genome-wide linkage analysis in an interval overlapping with the loci DFNB53 (COL11A2), DFNB66, and DFNB67. Fine mapping excluded DFNB53 and subsequently homozygous mutations were identified in the lipoma HMGIC fusion partner-like 5 (LHFPL5) gene, also named tetraspan membrane protein of hair cell stereocilia (TMHS) gene, which was recently shown to be mutated in the "hurry scurry" mouse and in two DFNB67-linked families from Pakistan. In one family, we found a homozygous one-base pair deletion, c.649delG (p.Glu216ArgfsX26) and in the other family we identified a homozygous transition c.494C>T (p.Thr165Met). Further screening of index patients from 96 Turkish ARNSHL families and 90 Dutch ARNSHL patients identified one additional Turkish family carrying the c.649delG mutation. Haplotype analysis revealed that the c.649delG mutation was located on a common haplotype in both families. Mutation screening of the LHFPL5 homologs LHFPL3 and LHFPL4 did not reveal any disease causing mutation. Our findings indicate that LHFPL5 is essential for normal function of the human cochlea.  相似文献   
30.
Introduction: Antimalarial medications are basal active drugs used for the treatment of various rheumatological conditions. Their common side‐effects include eye damage. Aim: The aim of this study is to determine the safety of antimalarial medications used for rheumatological conditions and the incidence of retinopathy. Material and methods: Eighty‐five patients with rheumatological conditions, who were followed in our rheumatology clinics between 2005 and 2009 while under chloroquine (CQ) and/or hydroxychloroquine (HQ) treatment were included in the study. Indirect ophthalmoscopic examination with 90 dioptry lens, frontal segment examination and macular visual area test were applied to all patients. Severity of retinopathy was evaluated as mild initial defect in the macula, or severe visual area loss. Results: Retinopathy findings were detected in 21 out of 85 patients (24.7%). Of these patients, 12 had mild initial defects while nine had severe visual area loss. Of 21 patients, eight were on HQ and 13 were on CQ treatment. Of the patients seen with findings of retinopathy, 17 had comorbid hypertension (HT) and six had diabetes mellitus (DM). Patients receiving CQ are under higher risk compared to those on HQ treatment (P = 0.001). Patient age, disease duration, HT and DM presence had no statistically significant effect on retinopathy development (P = 0.144, P = 0.305, P = 0.258, P = 0.395, respectively). Conclusion: The incidence of retinopathy among patients using antimalarial medications as observed in this study was relatively high. Based on these results, it is essential to emphasize the importance of close monitoring in patients receiving antimalarial medications and evaluation of visual findings before treatment initiation.  相似文献   
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