Longitudinal Evaluation of Radiopacity of Resin Composites: Influence of Photoactivation and Accelerated Photoaging.

This study aimed to assess longitudinally the radiopacity of resin composites under the influence of photoactivation and photoaging processes. Ten specimens (1 mm thick and 4 mm in diameter) of three different microhybrid resin composites, Filtek Z250 XT (R1), TPH 3 Spectrum (R2), and Opallis (R3), were prepared for this study. For longitudinal assessment of radiopacity, radiographic images were obtained five times. The first time (T1), the specimens were not photoactivated; the second time (T2), the specimens were photoactivated; and the next three times, photoaging was carried out, with images obtained at 24 hours (T3), 48 hours (T4), and 72 hours (T5) after this process. The photoaging was conducted using LED light (700 lumens, 9 W, 6400 k) under controlled environmental conditions at 37°C (±1°C) and 65% (±5%) relative humidity. The digital system DIGORA Optime was used. The digital images were measured using the histogram function, and then the pixel intensity values were converted into mmAl (the standard unit of radiopacity) using a linear regression function, with minimal adjustment of R2 ≥ 0.9. Data in mmAl were statistically analyzed using an analysis of variance (α=0.05). R2 resin composite showed higher values of radiopacity, R1 resin composite showed intermediate values, and R3 resin composite showed lower values. Only at T1 did the higher radiopacity of R2 composite differ significantly from other groups ( p = 0.0000). After application of treatments (photoactivation and photoaging), all radiopacity values were similar ( p-values to T2=0.0507, T3=0.0536, T4=0.0502, T5=0.0501) due to consecutive increase of radiopacity of R1 and R3 composites from T2. Photoactivation and photoaging processes influenced the radiopacity, but changes occurring in the degree of radiopacity were dependent on the composition and chemical characteristics of each composite used.

Evaluation of low-contrast perceptibility in dental restorative materials under the influence of ambient light conditions.

OBJECTIVES: This study aimed to assess how details on dental restorative composites with different radio-opacities are perceived under the influence of ambient light. METHODS: Resin composite step wedges (six steps, each 1-mm thick) were custom manufactured from three materials, respectively: (M1) Filtek™ Z350 (3M/ESPE, Saint Paul, MN); (M2) Prisma AP.H™ (Dentsply International Inc., Brazil) and (M3) Glacier(®) (SDI Limited, Victoria, Australia). Each step of the manufactured wedge received three standardized drillings of different diameters and depths. An aluminium (Al) step wedge with 12 steps (1-mm thick) was used as an internal standard to calculate the radio-opacity as pixel intensity values. Standardized digital images of the set were obtained, and 11 observers independently recorded the images, noting the number of noticeable details (drillings) under 2 dissimilar conditions: in a light environment (light was turned on in the room) and in low-light conditions (light in the room was turned off). The differences between images in terms of the number of details that were observed were statistically compared using ANOVA, Cronbach's alpha coefficient and Wilcoxon and Kruskal-Wallis tests, with a significance level setting of 5% (α = 0.05). RESULTS: The M2 showed higher radio-opacity, the M1 displayed intermediate radio-opacity and the M3 showed lower radio-opacity, respectively; however, all three were without significance (p > 0.05) compared with each other. The differences in radio-opacity resulted in a significant variation (p < 0.05) in the number of noticeable details in the image, which were influenced by characteristics of details, in addition to the ambient-light level. CONCLUSIONS: The radio-opacity of materials and ambient light can affect the perception of details in digital radiographic images.

Intrarenal pseudoaneurysm after percutaneous nephrolithotomy. Angiotomographic assessment and endovascular management.

We report a case of intrarenal pseudoaneurysm of the right kidney after percutaneous nephrolithotomy (PCNL) in supine position. Diagnosis was established by angiotomography with a 3-D reconstruction. Treatment was successfully achieved by endovascular occlusion using N-butyl-2-cyanoacrylate.

Intrarenal pseudoaneurysm after percutaneous nephrolithotomy: angiotomographic assessment and endovascular management

We report a case of intrarenal pseudoaneurysm of the right kidney after percutaneous nephrolithotomy (PCNL) in supine position. Diagnosis was established by angiotomography with a 3-D reconstruction. Treatment was successfully achieved by endovascular occlusion using N-butyl-2-cyanoacrylate.

Laparoscopic left radical nephrectomy and hand-assisted isthmectomy of a horseshoe kidney with renal cell carcinoma.

A 64-year-old woman presented with recurrent gross hematuria and intermittent left-sided pain. A CT scan revealed an 8-cm mass in the left moiety of a horseshoe kidney. A laparoscopic transperitoneal approach was employed to control the vessels and release the left moiety of the kidney and a hand-assisted approach was performed for isthmectomy using compression of normal parenchyma and monopolar electrocautery. Additional sutures were applied externally in isthmus through hand-assisted incision to enhance hemostasis. The patient was discharged on postoperative day 4 with no complications and no relapse after a 1-year follow-up. We conclude that our technique is safe, cheap and effective for this complex clinical entity.

Retrospective analysis of 31 cases of nasopalatine duct cyst.

OBJECTIVE: To perform a retrospective analysis of patients with nasopalatine duct cysts (NPDC) in Brazil and compare with previous analyses. MATERIALS AND METHODS: The files of the Laboratory of Oral Pathology (Minas Gerais Federal University) from 1966 to 1997 were reviewed. Demographic, clinical and histologic data of patients with nasopalatine duct cysts were collected. RESULTS: The mean age of patients with nasopalatine duct cysts at the time of diagnosis was 37.4 years and with a predilection for males. The majority of cases were asymptomatic. Histologically, non-keratinized stratified squamous epithelium alone or in combination with other epithelia was observed in 93% of the cases. Recurrence was not recorded. CONCLUSION: The demographic, histopathological, radiographic, and clinical data of the NPDC in our series are similar to previous studies in other populations.

[Familial myasthenia gravis: a case report in identical twins]. / Miastenia grave familiar: relato de caso em gêmeas idênticas.

To the best of our knowledge this is the seventh case report of monozygotic twins both affected by myasthenia gravis (MG). The monozygotism was proven by sex identity, blood group and HLA determinations ('O' Rh+, A2, A19.2, B40, CW3). One paternal aunt was also affected and the three cases have high titles of anti-acetylcholine receptor antibodies and anti-striated muscle antibodies, which indicate an acquired form of MG. After several myasthenic crises the twins are now doing well with corticosteroid therapy. The paternal aunt has a more benign form of MG, with ocular and limb involvement (grade IIa of Osserman) and was submitted to thymectomy. The authors discuss the use of corticosteroid for the infantile form of MG instead of thymectomy, based on the immaturity of the immune system in the young age. The use of other immunosuppressive drugs is not advisable because of potential hazardous development of neoplasms.