Analysis of the interfacial micromorphology and bond strength of adhesive systems to Er:YAG laser-irradiated dentin

This study evaluated the effects of different parameters of dentin irradiation with erbium-doped yttrium aluminum garnet (Er:YAG) laser on bond strength to dentin and analyzed the ultramorphological characteristics of resin–laser-irradiated dentin interfaces using a transmission electron microscope (TEM). Dentin surfaces were abraded with SiC paper (600 grit) or Er:YAG laser-irradiated (120/4, 140/6, 180/4, or 200/6 mJ/Hz). Three adhesive systems were tested: Single Bond Plus (3M ESPE), Clearfil Protect Bond (Kuraray Med.), and Clearfil Tri-S Bond (Kuraray Med.). Treatments were performed over flat dentin surfaces of human third molars. Specimens were stored in distilled water for 1 week or 6 months and prepared for a microtensile bond strength test and interfacial ultrastructure for analysis. Microtensile bond strength data (n?=?5) were analyzed with three-way analysis of variance. Irradiation with Er:YAG laser did not reduce the bond strength values for self-etching adhesives even after 6 months of water storage. The hybrid layer formation was observed only when the adhesives were applied to non-irradiated dentin (control group). Nanoleakage occurred in all resin–dentin interfaces using Single Bond Plus for both periods. Nanoleakage pattern and bond strength of self-etching adhesives to dentin were less affected by Er:YAG laser irradiation and by the 6-month storage in water than was those of the etch-and-rinse adhesive. TEM analysis revealed no hybridization when dentin was laser-irradiated. Clinical significance: Minimally invasive caries removal has been proposed. Nevertheless, bonding mechanisms to lased dentin are not entirely described. Knowing the interaction between the treated dentin and bonding agents and its behavior over time is of utmost importance for new technologies. Regarding that, two-bottle self-etching adhesive system provided a more consistent evidence of its better behavior when bonding to lased substrate.     

Discriminating sarcopenia in community-dwelling older women with high frequency of overweight/obesity: the São Paulo Ageing & Health Study (SPAH)

Summary

The criteria most used for the definition of sarcopenia, those based on the ratio between the appendicular skeletal muscle mass (ASM) and the square of the height (h²) underestimate prevalence in overweight/obese people whereas another criteria consider ASM adjusted for total fat mass. We have shown that ASM adjusted for fat seems to be more appropriate for sarcopenia diagnosis.

Introduction

Since the prevalence of overweight and obesity is a growing public health issue, the aim of this study was to evaluate the prevalence and risk factors associated with sarcopenia, based on these two criteria, among older women.

Methods

Six hundred eleven community-dwelling women were evaluated by specific questionnaire including clinical data. Body composition and bone mineral density were evaluated by dual X-ray absorptiometry. Logistic regression models were used to identify factors independently related to sarcopenia by ASM/h² and ASM adjusted for total fat mass criteria.

Results

The prevalence of overweight/obesity was high (74.3 %). The frequency of sarcopenia was lower using the criteria of ASM/h² (3.7 %) than ASM adjusted for fat (19.9 %) (P?<?0.0001). We also note that less than 5 %(1/23) of sarcopenic women, according to ASM/h², had overweight/obesity, whereas 60 % (74/122) of sarcopenic women by ASM adjusted for fat had this complication. Using ASM/h², the associated factors observed in regression models were femoral neck T-score (OR?=?1.90; 95 % CI 1.06–3.41; P?=?0.03) and current alcohol intake (OR?=?4.13, 95 % CI 1.18–14.45, P?=?0.03). In contrast, we have identified that creatinine (OR?=?0.21; 95 % CI 0.07–0.63; P?=?0.005) and the White race (OR?=?1.81; 95 % CI 1.15–2.84; P?=?0.01) showed a significant association with sarcopenia using ASM adjusted for fat.

Conclusions

In women with overweight/obesity, ASM adjusted for fat seems to be the more appropriate criteria for sarcopenia diagnosis. This finding has relevant public health implications, considering the high prevalence of overweight/obesity in older women.     

Report of a case of solitary fibrous tumour of the orbit

Background

Solitary fibrous tumors of the orbit are uncommon lesions, only one relatively large series having been published. Neoplasms, formerly considered as separate entities, including hemangiopericytoma, are presently encompassed as solitary fibrous tumors, a unifying designation. There is a tendency towards recurrence and some cases are malignant. Their rarity justifies the publication of new cases, in order to increase the amount of information about this pathological entity.

Case report

A 40-year-old female patient developed swelling in the left lower lid and after slow progression of the symptom during 2 years, presented herself to our elective surgery service. Image exams showed a 20-mm encapsulated tumor. Surgical treatment was performed: complete excision, made difficult by the growth of the lesion amid the inferior rectus and inferior oblique muscles. Histopathological and immunochemical examinations with CD34 positivity, diagnosed a solitary fibrous tumor, without suggestive signs of malignancy. After a follow-up of 40 months, no recurrence has been detected.

Discussion

Solitary fibrous tumors, though uncommon, should be considered in the differential diagnosis of orbital expansive lesions. The key point to diagnosis is finding CD34 positivity in immunohistochemical examination. Such tumors have a tendency for recurrence, even after more than 5 years.     

Localization of the hand motor area by arterial spin labeling and blood oxygen level‐dependent functional magnetic resonance imaging

The new clinically available arterial spin labeling (ASL) perfusion imaging sequences present some advantages relatively to the commonly used blood oxygen level‐dependent (BOLD) method for functional brain studies using magnetic resonance imaging (MRI). In particular, regional cerebral blood flow (CBF) changes are thought to be more directly related with neuronal activation. In this study, we aimed to investigate the accuracy of the functional localization of the hand motor area obtained by simultaneous CBF and BOLD contrasts provided by ASL functional MRI (fMRI) and compare it with a standard BOLD fMRI protocol. For this purpose, we measured the distance between the center of gravity of the activation clusters obtained with each contrast (CBF, BOLD_ASL, and Standard BOLD) and 11 positions defined on a well‐established anatomical landmark of the hand motor area (the omega in the axial plane of the precentral gyrus). We found that CBF measurements were significantly closer to the anatomical landmark than the ones obtained using either simultaneous BOLD_ASL or standard BOLD contrasts. Moreover, we also observed reduced intersubject variability of the functional localization, as well as percent signal change, for CBF relative to both BOLD contrast measurements. In conclusion, our results add further evidence in support to the notion that CBF provides a more accurate localization of motor activation than BOLD contrast, indicating that ASL may be an appropriate technique for clinical fMRI studies. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.