Embrasure aligner fit and thickness in 3D-printed and thermoformed aligners: a microcomputed tomography study.

Background: The theory of “functional progesterone withdrawal” explains the role of progesterone prior to delivery. Previous studies mentioned the existence of progesterone regulation in the cervix that plays a role in maintaining the integrity of the cervix and cervical ripening. Cervical progesterone levels relate to activities of progesterone at the cervix, compared to its amount in circulation. The objective of this study was to measure cervical mucus progesterone levels and its correlation to plasma progesterone levels in pregnancy. Methods: This was a cross-sectional study conducted in January-September 2010 at Persahabatan Hospital. The subjects were pregnant women in the 28th – 34th weeks of gestational age. In total, 72 subjects who met the criteria were divided into normal pregnancy group and preterm labor group. The cervical and plasma progesterone levels were measured using The Advia Centaur® Progesterone kit, which is a commercial immunoassay with direct chemiluminescence method. Results: There was a positive correlation (r=0.539) between cervical progesterone levels with plasma progesterone levels in the preterm labor group. There was no correlation between cervical progesterone levels with plasma progesterone levels in the normal pregnancy group. Conclusion: This study showed that cervical progesterone levels could be measured through cervical mucus. A significant positive correlation was found by this study between cervical progesterone levels and plasma progesterone levels in the preterm labor group. This study is expected to provide new insights for understanding the metabolism and the role of progesterone in maintaining cervical integrity during pregnancy, and its relation to prevention of preterm birth.

Background: Theory of “functional progesterone withdrawal” explains the role of progesterone prior to delivery. Previous studies mentioned the existence of progesterone regulation in the cervix that plays a role in maintaining the integrity of the cervix and cervical ripening. Cervical progesterone levels relate to activities of progesterone at the cervix, compared to its amount in circulation. The objective of this study was to measure cervical mucus progesterone levels and its correlation to plasma progesterone levels in pregnancy. Methods: This was a cross sectional study conducted in January-September 2010 at Persahabatan Hospital. The subjects were pregnant woman in the 28th – 34th weeks of gestational age. In total, 72 subjects who met the criteria were divided into normal pregnancy group and preterm labor group. The cervical and plasma progesterone levels were measured using The Advia Centaur® Progesterone kit, which is a commercial immunoassay with direct chemiluminescence method. Results: There was positive correlation (r=0.539) between cervical progesterone levels with plasma progesterone levels in the preterm labor group. There was no correlation between cervical progesterone levels with plasma progesterone levels in the normal pregnancy group. Conclusion: This study showed that cervical progesterone levels could be measured through cervical mucus. A significant positive correlation was found by this study between cervical progesterone levels and plasma progesterone levels in the preterm labor group. This study is expected to provide new insights for understanding the metabolism and the role of progesterone in maintaining cervical integrity during pregnancy, and its relation to prevention of preterm birth.

To investigate the incidence and cause of severe visual loss following use and removal of intraocular silicone oil (SiO) after uncomplicated vitrectomy and SiO injection for primary rhegmatogenous retinal detachment (RRD). Consecutive case series of 216 patients operated with vitrectomy for primary RRD in 2004-2005. In 162 eyes, SiO (5500 centiStoke) had been used as intravitreal tamponade and in 54 eyes gas (perflouropropane, C(3) F(8) ) had been used. Following chart review, we identified 16 eyes in 16 patients (nine SiO eyes, seven gas eyes) with macula-on and documented visual acuity ≥6/12 before surgery, where SiO had been removed, cataract surgery performed and no re-detachment had occurred. Examinations included best-corrected visual acuity (BCVA) and high-definition optical coherence tomography (OCT) of the macular area. Preoperative characteristics were identical between SiO and gas eyes. Postoperative BCVA was significantly worse in SiO eyes (>6/24) compared to gas eyes (>6/7.5), p = 0.005. Three of 9 (33%) SiO eyes had final BCVA ≤6/60 and 67% had final BCVA ≤6/12. No gas eyes had final BCVA <6/9. Macular OCT revealed thinning of inner retinal layers in SiO-operated eyes (5148 pixels) compared to gas-operated eyes (6897 pixels), p < 0.002. No other visually significant structural differences were found. Severe visual loss after SiO use was observed in 1/3 of patients with otherwise good visual potential. The visual loss was associated with a significant reduction in inner retinal thickness indicating neuronal cell loss in the macular area as a possible explanation.

Measurement of cervical multifidus contraction pattern with ultrasound imaging

Time-related changes in skin thickness have been evaluated in the pig using a noninvasive ultrasound technique after exposure to a range of single doses of 0.97 MeV beta particles from (170)Tm plaques. The reduction in relative skin thickness developed in two phases; the separation into two phases was statistically justified only after 120 Gy (P = 0.04). The first phase was between 12 weeks and 24 weeks after irradiation. No further changes were seen until 48-60 weeks after irradiation, when a second phase of skin thinning was observed. No further changes in relative skin thickness were seen in the follow-up period of 104 weeks. The timing of these phases of relative skin thinning was totally independent of the radiation dose; however, the severity of each phase of radiation-induced skin thinning was related to the dose. The pattern of changes was similar to that reported previously after irradiation with 2.27 MeV beta particles from (90)Sr/(90)Y, but the degree of dermal thinning was less for a similar skin surface dose. From a comparison of the depth-dose distribution of the beta particles from the two radionuclides, it was concluded that the target cell population responsible for both the first and second phase of skin thinning in pig skin after irradiation may be located at approximately 800 microm depth. This corresponds to an area in the reticular dermis in pig skin and may be the appropriate site at which to measure the average dose to the dermal tissue.

To assess factors that may be associated with buccal bone changes adjacent to maxillary first molars after rapid maxillary expansion (RME) and fixed appliance therapy. Pretreatment (T1) and posttreatment (T2) cone-beam computed tomography scans were obtained from 45 patients treated with RME and preadjusted edgewise appliances. Buccal alveolar bone thickness was measured adjacent to the mesiobuccal root of the maxillary first molar 4 mm, 6 mm, and 8 mm apical to the cementoenamel junction, and anatomic defects were recorded. Paired and unpaired t-tests were used to compare alveolar bone thickness at T1 and T2 and to determine whether teeth with posttreatment anatomic defects had thinner initial bone. Correlation analyses were used to examine relationships between buccal alveolar bone thickness changes and amount of expansion, initial bone thickness, age at T1, postexpansion retention time, and treatment time. There was a statistically significant reduction in buccal alveolar bone thickness from T1 to T2. Approximately half (47.7%) of the teeth developed anatomic defects from T1 to T2. These teeth had significantly thinner buccal bone at T1. Reduction in alveolar bone thickness was correlated with only one tested variable: initial bone thickness. RME and fixed-appliance therapy can be associated with significant reduction in buccal alveolar bone thickness and an increase in anatomic defects adjacent to the expander anchor teeth. Anchor teeth with greater initial buccal bone thickness have less reduction in buccal bone thickness and are less likely to develop posttreatment anatomic defects of buccal bone.

To correlate the microaneurysmal closure rate measured on fundus fluorescein angiography (FFA) with reduction in macular thickness observed on optical coherence tomography (OCT) following laser photocoagulation of diabetic macular edema. A prospective observational case series. Fifty patients (50 eyes) of type II diabetes mellitus with clinically significant macular oedema (CSME) underwent focal/grid laser photocoagulation. OCT and FFA were performed at baseline and at 2 and 12 weeks following laser photocoagulation to measure the change in macular thickness and the number of leaking microaneurysms respectively. Statistical analysis was performed using paired-ttest and Pearson's correlation test. A significant reduction in macular thickness was seen at both 2 (P=0.02) and 12 weeks (P<0.0001), most remarkably in the central 1 mm quadrant. However, microaneurysm closure was only 0.67% at 2 weeks, which increased to 89.6% by 12 weeks. The change in retinal thickness correlated significantly with the decrease in the number of leaking microaneurysms at 12 weeks (r=0.597, P<0.0001), but not at 2 weeks (r=-0.228, P=0.112). On OCT, the final reduction in retinal thickness achieved at 12 weeks from baseline correlated significantly with the initial decrease in retinal thickness at 2 weeks (r=0.66, P<0.0001). However, on FFA, the final closure rate of leaking microaneurysms at 12 weeks from baseline did not correlate with the initial closure rate at 2 weeks (r=-0.039, P=0.413). Following laser photocoagulation for CSME, an OCT at 2 weeks is more informative and better correlates with the final outcome than an FFA at 2 weeks.

Nano-coated long-period gratings for detection of sub-nanometric changes in thin-film thickness

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Time-related changes in pig skin thickness have been evaluated using a non-invasive ultrasound technique after exposure to a range of single doses of 90Sr/90Y beta-rays. The reduction in relative skin thickness developed in two distinct phases: the first was between 12 and 20 weeks postirradiation. No further changes were then seen until 52 weeks postirradiation when a second phase of skin thinning was observed. This was complete after 76 weeks and no further changes in relative skin thickness were seen in the maximum follow up period of 129 weeks. The timings of these phases of damage were independent of the radiation dose, however, the severity of both phases of radiation-induced skin thinning were dose related.

To assess the effect of intravitreal bevacizumab on diabetic macular oedema (DMO) and retinal vessel calibres. We performed a consecutive case series study in which 10 consecutive eyes with diffuse DMO, two of which had not previously been treated, received an intravitreal injection of bevacizumab 1 mg, which was followed by two more injections at 6-week intervals. Fundus photography and optical coherence tomography (OCT) were carried out at baseline immediately before injection and at 1, 2.5 and 4 months after the first injection. Outcome measures were best corrected visual acuity (BCVA) in Early Treatment Diabetic Retinopathy Study letters, macular volume, foveal subfield thickness and vessel diameter measurement. Intravitreal administration of bevacizumab was followed by a mean increase in BCVA of 7.3 +/- 17 (mean +/- standard deviation) letters between baseline and month 4, which was 1 month after the last injection (p < 0.0001). This was accompanied by a reduction in mean macular volume from 9.90 +/- 1.9 mm(3) to 8.96 +/- 2.4 mm(3) (p = 0.002) and in foveal subfield thickness from 447 +/- 117 microm to 388 +/- 117 microm (p = 0.03). Two eyes with early proliferative diabetic retinopathy lost all signs of proliferation without any evidence of fibrosis. Although there was a trend towards vasoconstriction, the changes in vessel diameters (arteries and veins) after 4 months of intravitreal Avastin injection were not statistically significant (p = 0.9 and p = 0.17, respectively). Foveal thickness in non-injected fellow eyes with DMO changed from 428 +/- 153 microm at baseline to 383 +/- 151 microm at 4 months (p = 0.1), which did not reach statistical significance. Intravitreal bevacizumab 1 mg every 6 weeks was followed by a moderate reduction in DMO without normalization of foveal and macular thickness. Our observations suggest that a larger study where patients are examined sooner after injection is needed to elucidate the potential relationship between changes in retinal vessel diameters and thickness changes in DMO.

Thickness changes in model futons contains two kinds of recycled fiber assemblies made from knitted sweaters fabrics were evaluated by the repeated compression test. Initial thickness under a constant weight for the recycled fiber assemblies was smaller than for pure wool and wool-blended samples. There were less reduction in thickness of the model futons filled with recycled fiber assemblies compared with the model futons filled with wool fiber assemblies during the repeated compression test. The yarns remained in the recycled fiber mass contributed to the less reduction in thickness of model futons. For the wool blend recycled sample, the compression rigidity was small compared with that of unused wool and wool-blended fiber assemblies, because recycled fiber assemblies made from sweaters consist of relatively fine wool fibers. The recycled sample showed less reduction in thickness of model futons and expected to be soft during use. It was confirmed that this material was suitable for the filling of futons and cushions.

ObjectivesTo evaluate, through (OCT), alterations in retinal thickness, secondary to use of ethambutol in the treatment of patients with tuberculosis. In addition to studying the use of simpler semiological tools, such as Amsler and Ishihara, in the screening of these cases.MethodsThirty patients with ethambutol were recruited from the reference service of tuberculosis treatment at the Federal University of Espírito Santo from May 2015 to July 2016. After clinical history, the following parameters were analyzed; best corrected visual acuity, biomicroscopy, tonometry, photomotor reflex testing, Ishihara test, Amsler’s grid test, color digital retinography and optical coherence tomography with CIRRUS HD-OCT (Humphrey-Zeiss) every 2 months during treatment with ethambutol. They were divided into two groups according to the treatment: (1) standard group, two months of ethambutol; (2) extended group, nine to twelve months of ethambutol.ResultsThere was a significant reduction in OCT thickness between the pre and post treatment times in ten eyes of the extended group, mean reduction of 7,8 microns and in seven eyes of the standard group, with an average of 5.57 microns. During the study, a significant reduction of retinal thickness was observed in both groups at two months of treatment, and the delta percentage was higher in those patients who presented reduction of visual acuity and / or change in the Ishihara test.ConclusionThere was a significant reduction in the thickness of the nerve fiber layer by OCT in the patients studied, being more pronounced in those submitted to the extended treatment regimen. This reduction was observed two months after the start of therapy, and was more significant in the cases that presented changes in the Ishihara test.

The effects of intermittent intraperitoneal ethanol exposure (3 g/kg body weight twice daily) on hippocampal cells of adult rats were examined after a 1-month exposure period. Continuous oral exposure to ethanol in the drinking water (20%) over the same time period was used for comparison. Pyramidal cells from the CA3 region and granule cells from the dentate gyrus were also qualitatively assessed using electron microscopy. One month of intermittent, peaking, exposure induced a significant loss of CA2-CA3 pyramidal cells and an increase in the number of lipofuscin granules in the remaining cells. A significant reduction in thickness of the dentate gyrus granule cell layer was also seen in the same animals. No significant reduction in pyramidal cell number or granule cell layer thickness was seen in continuously orally exposed animals in spite of a higher total ethanol intake. These studies thus demonstrate the harmful effect of intermittent high ethanol peaks and repeated withdrawal phases on hippocampal cells of the mammalian brain and emphasize the importance of considering the differential effects of different ethanol exposure patterns when assessing ethanol-induced cellular damage.

Background: The neurovascular dysfunction appears to be related to the development of migraines and it could be possible that hypoperfusion might also involve other areas besides brain, including the retina. Numerous studies have analyzed the ability of optical coherence tomography (OCT) to detect retinal nerve fiber layer (RNFL) thickness abnormalities and changes in migraine, but the results have not always been consistent. Therefore, we carried out a meta-analysis to evaluate the RNFL thickness measured with OCT in migraine.Methods: Case–control studies were selected through an electronic search of the Cochrane Controlled Trials Register, PUBMED and EMBASE. For the continuous outcomes, we calculated the weighted mean difference (WMD) and 95% confidence interval (CI). The statistical analysis was performed by RevMan 5.0 software.Results: Six case–control studies were included in the present meta-analysis, containing a total of 432 eyes in migraine patients and 288 eyes in healthy controls. The results of our study showed that there was a significant reduction in average RNFL thickness in patients with migraine compared to healthy controls (WMD = −3.67, 95% CI: −6.84 to −0.49, p = 0.02). Additionally, differences of RNFL thickness in superior quadrant (WMD = −9.23, 95% CI: −15.63 to −2.82, p = 0.005), inferior quadrant (WMD = −3.47, 95% CI: −6.73 to −0.22, p = 0.04), nasal quadrant (WMD = −3.86, 95% CI: −7.10 to −0.61, p = 0.02) and temporal quadrant (WMD = −3.10, 95% CI: −5.05 to −1.15, p = 0.002) were all significant between the two groups.Conclusions: Our meta-analysis found that RNFL thickness in the migraine patients was thinner than that in the healthy control group. Given the limited sample size, further investigations are needed to validate these findings.