Haemorrhagic low-grade fibromyxoid sarcoma: MR findings in two young women

Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft-tissue sarcoma characterised by a deceptively bland histological appearance and a paradoxically aggressive behaviour. LGFMS usually presents in young-to-middle-aged adults as a painless, slow-growing mass with the potential for local recurrence and metastasis despite low-grade histology. Several case reports have described variable MR findings of LGFMS without haemorrhage or necrosis. We report here on the MR findings in two young women with haemorrhagic LGFMS in the thigh.

Nano-scaled Pt/Ag/Ni/Au contacts on p-type GaN for low contact resistance and high reflectivity

We synthesized the vertical-structured LED (VLED) using nano-scaled Pt between p-type GaN and Ag-based reflector. The metallization scheme on p-type GaN for high reflectance and low was the nano-scaled Pt/Ag/Ni/Au. Nano-scaled Pt (5 A) on Ag/Ni/Au exhibited reasonably high reflectance of 86.2% at the wavelength of 460 nm due to high transmittance of light through nano-scaled Pt (5 A) onto Ag layer. Ohmic behavior of contact metal, Pt/Ag/Ni/Au, to p-type GaN was achieved using surface treatments of p-type GaN prior to the deposition of contact metals and the specific contact resistance was observed with decreasing Pt thickness of 5 A, resulting in 1.5 x 10(-4) ohms cm2. Forward voltages of Pt (5 A)/Ag/Ni contact to p-type GaN showed 4.19 V with the current injection of 350 mA. Output voltages with various thickness of Pt showed the highest value at the smallest thickness of Pt due to its high transmittance of light onto Ag, leading to high reflectance. Our results propose that nano-scaled Pt/Ag/Ni could act as a promising contact metal to p-type GaN for improving the performance of VLEDs.

Performance of GaN vertical light emitting diodes using wafer bonding process with Al-alloyed graphite substrate

We report on the vertical-structure light emitting diodes (VLEDs) fabricated with wafer bonding method using Al-alloyed graphite and Si supporter. VLEDs with Al-alloyed graphite produced no crack during/after laser lift-off (LLO) techniques while the wafer crack took place using Si supporter because of the difference of thermal expansion coefficients between Si and sapphire. The performance of VLEDs with wafer bonding method using Al-alloyed graphite supporter was compared to those fabricated by Cu plating methods. The output power of the chips with wafer bonding method was nearly same as the one with Cu-plating method. However, the forward voltage of VLEDs with wafer bonding method was higher than those with Cu-plating method. In the terms of reliabilities the wafer bonding process is more preferable to Cu-plating and our report proposes that Al-alloyed graphite could be one of promising candidates for the supporters in wafer bonding process.

Measurement limits to 134Cs concentration in soil

We investigate the caesium concentrations in soils in mountain areas near Gori nuclear power plant in Korea, focusing on the measurement limits to the (134)Cs. In order to lower the minimum detectable amount (MDA) of activity for the (134)Cs, we have used the ammonium molybdophosphate (AMP) precipitation method to get rid of the (40)K existing in natural radioactivity, which reduces the MDA activity about 10 times smaller than those without the AMP precipitation method. The MDA results for the (134)Cs were found to be in the range between 0.015 and 0.044 Bq/kg-dry weight. In order to diminish the background, we also have measured a part of the soil samples in Yangyang, a small town in the east coast of Korea. However, it turns out that in order to detect the (134)Cs in the samples the MDA should be reduced to the level of mBq/kg-dry weight.

Histiocytic necrotizing lymphadenitis in the context of systemic lupus erythematosus (SLE): Is histiocytic necrotizing lymphadenitis in SLE associated with skin lesions?

Histiocytic necrotizing lymphadenitis (HNL), or Kikuchi's disease, is a benign and self-limiting lymphadenopathy that typically affects young Asian females. It presents with lymphadenopathy, usually cervical, accompanied by fever, chills and leukopenia. Although the association between systemic lupus erythematosus (SLE) and HNL is rare, the number of reports of HNL in SLE patients is increasing. We present nine cases of HNL in patients with SLE. Among the seven patients with diverse skin manifestations, three had skin manifestations that were histologically compatible with SLE. A review of previous reports in the literature showed that cutaneous involvement was commonly found in HNL in association with SLE. In the patients who had simultaneous onset of both diseases, lupus flare-ups were commonly observed. We suggest that HNL in SLE patients is associated with cutaneous manifestations. This report contributes to our understanding of the relationship between these diseases.

Observation of B(s)⁰→J/ψf₀(980) and evidence for B(s)⁰→J/ψf₀(1370)

We report the observation of B(s)⁰→J/ψf₀(980) and evidence for B(s)⁰→J/ψf₀(1370), which are CP eigenstate decay modes. These results are obtained from 121.4 fb⁻¹ of data collected at the Υ(5S) resonance with the Belle detector at the KEKB e(+)e⁻ collider. We measure the branching fractions B(B(s)⁰→J/ψf₀(980); f₀(980)→π(+)π⁻)=(1.16(-0.19)(+0.31)(stat)(-0.17)(+0.15)(syst)(-0.18)(+0.26)(N(B(s)((*))B(s)((*)))))×10⁻⁴ with a significance of 8.4σ, and B(B(s)⁰→J/ψf₀(1370); f₀(1370)→π(+)π⁻)=(0.34(-0.14)(+0.11)(stat)(-0.02)(+0.03)(syst)(-0.05)(+0.08)(N(B(s)((*))B(s)((*)))))×10⁻⁴ with a significance of 4.2σ. The last error listed is due to uncertainty in the number of produced B(s)((*))B(s)((*)) pairs.

An in-mold packaging process for plastic fluidic devices

Micro or nanofluidic devices have many channel shapes to deliver chemical solutions, body fluids or any fluids. The channels in these devices should be covered to prevent the fluids from overflowing or leaking. A typical method to fabricate an enclosed channel is to bond or weld a cover plate to a channel plate. This solid-to-solid bonding process, however, takes a considerable amount of time for mass production. In this study, a new process for molding a cover layer that can enclose open micro or nanochannels without solid-to-solid bonding is proposed and its feasibility is estimated. First, based on the design of a model microchannel, a brass microchannel master core was machined and a plastic microchannel platform was injection-molded. Using this molded platform, a series of experiments was performed for four process or mold design parameters. Some feasible conditions were successfully found to enclosed channels without filling the microchannels for the injection molding of a cover layer over the plastic microchannel platform. In addition, the bond strength and seal performance were estimated in a comparison with those done by conventional bonding or welding processes.

The feasibility of endoscopic submucosal dissection for rectal carcinoid tumors: comparison with endoscopic mucosal resection

BACKGROUND AND STUDY AIMS

Rectal carcinoid tumors are often found incidentally during screening colonoscopy and can be resected using various endoscopic techniques. This study aimed to compare the safety and efficacy of endoscopic submucosal dissection (ESD) with endoscopic mucosal resection (EMR) for rectal carcinoid tumors.

PATIENTS AND METHODS

Between January 2003 and June 2009, 74 patients (74 lesions) underwent either EMR (n = 28) or ESD (n = 46) for rectal carcinoid tumors. The rate of endoscopic complete resection, pathological complete resection, procedure complications, and tumor recurrence were analyzed retrospectively.

RESULTS

The endoscopic complete resection rate was significantly higher in the ESD group (46 lesions, 100 %) compared with the EMR group (25 lesions, 89.3 %) ( P = 0.049). The pathological complete resection rate was higher in the ESD group (38 lesions, 82.6 %) compared with the EMR group (18 lesions, 64.3 %); however, this difference was borderline significant ( P = 0.067). Overall complication rate was not significantly different between the EMR group (3.6 %) and the ESD group (6.3 %). There was one case of remnant lesion in the EMR group, which was managed by ESD, and no recurrence has been detected in either the EMR or ESD groups.

CONCLUSION

This study suggests that ESD might be a feasible treatment technique for small rectal carcinoid tumors. It showed superior efficacy and comparable safety to EMR.

Health behaviour and quality of life in Korean adults with respiratory disease: National Health Survey, 2005

OBJECTIVES

To describe disease management, health behaviour, psychological health and quality of life (QOL) in people with chronic respiratory disease (CRD).

METHODS

We analysed data from 798 adults with CRD drawn from the Korean National Health and Nutrition Examination Survey (KNHANES) 2005: 514 subjects with asthma alone, 258 with chronic obstructive pulmonary disease (COPD) alone, and 56 with asthma and COPD.

RESULTS

Disease management and health behaviour in this cohort were poor. One third of the cohort was not seeking any medical treatment, although many were currently experiencing respiratory symptoms. Twenty-six per cent of the subjects were current smokers who averaged 0.8 packs/day. More than half of the subjects did not exercise, only half of the subjects had regular health examinations and one third of the subjects did not get enough sleep. The study population exhibited poor psychological indices, functional health status and QOL. The combined asthma and COPD group was characterised by an increased frequency of problems related to functional status and QOL.

CONCLUSIONS

People with CRD are at high risk for functional limitations, unhealthy behaviour, poor mental status and poor QOL. A comprehensive disease management programme for people with CRD should be developed using collaborative team efforts.

Intratendinous ganglion cyst of the semimembranosus tendon

Intratendinous ganglion cyst is a very rare lesion with an unknown aetiology that originates within the tendon. We encountered a case of 43-year-old woman who complained of a palpable, non-tender mass in the thigh with increasing swelling. An intratendinous ganglion cyst in the semimembranosus tendon of the lower extremity was diagnosed and located by ultrasound and MRI. Nine months after a surgical excision, there were recurrent ganglion cysts along the semimembranosus tendon. We describe this case with a review of the relevant literature.

Evidence for a new resonance and search for the Y(4140) in the gammagamma-->phiJ/psi process

The process gammagamma-->phiJ/psi is measured using a data sample of 825 fb{-1} collected with the Belle detector. A narrow peak of 8.8{-3.2}{+4.2} events, with a significance of 3.2 standard deviations including systematic uncertainty, is observed. The mass and natural width of the structure [named X(4350)] are measured to be [4350.6{-5.1}{+4.6}(stat)+/-0.7(syst)] MeV/c{2} and [13{-9}{+18}(stat)+/-4(syst)] MeV, respectively. The product of its two-photon decay width and branching fraction to phiJ/psi is [6.7{-2.4}{+3.2}(stat)+/-1.1(syst)] eV for J{P}=0{+}, or [1.5{-0.6}{+0.7}(stat)+/-0.3(syst)] eV for J{P}=2{+}. No signal for the Y(4140)-->phiJ/psi structure reported by the CDF Collaboration in B-->K{+}phiJ/psi decays is observed, and limits of Gamma_{gammagamma}(Y(4140))B(Y(4140)-->phiJ/psi)<41 eV for J{P}=0;{+} or <6.0 eV for J{P}=2{+} are determined at the 90% C.L. This disfavors the scenario in which the Y(4140) is a D{s}{*+}D{s}{*-} molecule.

Failure of a glass ionomer to remineralize apatite-depleted dentin

Remineralization of demineralized dentin lesions adjacent to glass-ionomer cements (GICs) has been reported in the literature. This study tested the hypothesis that a strontium-based GIC can remineralize completely demineralized dentin by nucleation of new apatite crystallites within an apatite-free dentin matrix. Human dentin specimens were acid-etched, bonded with Fuji IX(GP), and immersed in a calcium-and-phosphate-containing 1.5X simulated body fluid (SBF) for 1-4 months. Polyacrylic acid and polyvinylphosphonic acid biomimetic analogs were added to the SBFs to create 2 additional remineralization media. Specimens were processed by transmission electron microscopy (TEM). No apatite deposition could be identified in the completely demineralized dentin in any of the specimens immersed in the 3 remineralization media, despite TEM/EDX evidence of diffusion of ions specific to the strontium-based GIC into the demineralized dentin. The hypothesis was rejected; mineral concentration alone is not a sufficient endpoint for assessing the success of contemporary remineralization strategies.

Measurement of |V{ub}| from inclusive charmless semileptonic B decays

We present the partial branching fraction for inclusive charmless semileptonic B decays and the corresponding value of the Cabibbo-Kobayashi-Maskawa matrix element |V{ub}|, using a multivariate analysis method to access approximately 90% of the B-->X{u}lnu phase space. This approach dramatically reduces the theoretical uncertainties from the b-quark mass and nonperturbative QCD compared to all previous inclusive measurements. The results are based on a sample of 657x10{6} BB[over ] pairs collected with the Belle detector. We find that DeltaB(B-->X{u}lnu;p(l){*B}>1.0 GeV/c)=1.963x(1+/-0.088{stat}+/-0.081{syst})x10{-3}. Corresponding values of |V{ub}| are extracted using several theoretical calculations.

Measurement of inclusive radiative B-meson decays with a photon energy threshold of 1.7 GeV

Using 605 fb(-1) of data collected at the Upsilon(4S) resonance we present a measurement of the inclusive radiative B-meson decay channel, B-->X(s)gamma. For the lower photon energy thresholds of 1.7, 1.8, 1.9, and 2.0 GeV, as defined in the rest frame of the B meson, we measure the partial branching fraction and the mean and variance of the photon energy spectrum. At the 1.7 GeV threshold we obtain the partial branching fraction BF(B-->X(s)}gamma)=(3.45+/-0.15+/-0.40)x10(-4), where the errors are statistical and systematic.

Wildfire of Soybean Caused by Pseudomonas syringae pv. tabaci, a New Disease in Korea

In 2006 and 2007, a new bacterial disease was observed in field-cultivated soybeans in Boeun District and Munkyung City of Korea. The disease caused severe blighting of soybean (Glycine max) leaves. Soybean leaves in fields showed yellowish spots with brown centers. Brown and dead areas of variable size and shape were surrounded by wide, yellow haloes with distinct margins. Spots might coalesce and affected leaves fell readily. Seven bacterial strains were isolated from chlorotic areas of soybean leaves and all produced white colonies on trypticase soy agar. With the Biolog Microbial Identification System, version 4.2, (Biolog Inc., Hayward, CA) all strains and Pseudomonas syringae pv. tabaci CFBP2106^T were identified as P. syringae pv. tabaci with a Biolog similarity index of 0.28 to 0.52 and 0.48 after 24 h. Pathogenicity of the strains (three plants per strain) on soybean leaves at the V5 stage (cv. Hwanggeum) was confirmed by rub inoculation with bacterial suspensions (1 × 10⁸ CFU/ml) in sterile distilled water on the lesions cut 1 cm long on the upper side of the leaves with razor blades and by pinprick on 3-week-old leaves of tobacco (Nicotiana tabacum cv. Samsun) in the greenhouse. Wildfire symptoms on the soybean leaves and faint halos on tobacco leaves were observed 4 days after inoculation. The identification of reisolated bacterial strains was confirmed with the metabolic fingerprintings on Biolog. LOPAT tests (1) and phenotypic characteristics (3) of the strains were similar to those of the CFBP2106^T. Colonies were levan positive, oxidase negative, potato soft rot negative, arginine dihydrase negative, and tobacco hypersensitivity negative. All strains were gram-negative, aerobic rods with a polar flagellum. Strains were negative for esculin hydrolysis, gelatin liquefaction, urea production, accumulation of poly-β-hydroxy butyrate, starch hydrolysis, ornithine dihydrolase, lysine dihydrolase, growth at 37°C, utilization of geraniol, benzoate, cellobiose, sorbitol, trehalose, l-rhamnose, and adonitol. Positive reactions were catalase and arbutin hydrolysis, utilization of sorbitol, d-arabinose, and dl-serine. The strains were variable in utilization of mannitol, sucrose, and d-arabinose. The 1,472-bp PCR fragments of strains, BC2366 (GenBank Accession No. FJ755788) and BC2367 (No. FJ755789) was sequenced using 16S rDNA universal primers (2). The sequences shared 100% identity with the analogous sequences of P. syringae pv. glycenea (GenBank Accession No. AB001443) available in NCBI databases. Based on the phenotypic, genetic, and pathological characteristics, all strains were identified as P. syringae pv. tabaci. To our knowledge, this is the first report of P. syringae pv. tabaci causing wildfire on soybean in Korea. References: (1) R. A. Lelliott et al. J. Appl. Bacteriol. 29:470, 1966. (2) I.-S. Myung et al. Plant Dis. 92:1472, 2008. (3) N. W. Schaad et al., eds. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society, St. Paul, MN, 2001.

Measurement of the differential branching fraction and forward-backward asymmetry for B --> K(*)l+l-

We study B --> K(*)l+l- decays (l = e, mu) based on a data sample of 657 x 10(6) BB pairs collected with the Belle detector at the KEKB e+e- collider. We report the differential branching fraction, isospin asymmetry, K* polarization, and the forward-backward asymmetry (A(FB)) as functions of q2 = M(ll)(2)c2. The fitted A(FB) spectrum exceeds the standard model expectation by 2.7 standard deviations. The measured branching fractions are B(B --> K*l+l-) = (10.7(-1.0)(+1.1) +/- 0.9) x 10(-7) and B(B --> Kl+l-) = (4.8(-0.4)(+0.5) +/- 0.3) x 10(-7), where the first errors are statistical and the second are systematic, with the muon to electron ratios R(K*) = 0.83 +/- 0.17 +/- 0.08 and R(K) = 1.03 +/- 0.19 +/- 0.06.

Where has the tumor gone? The characteristics of cases of negative pathologic diagnosis after endoscopic mucosal resection

BACKGROUND AND STUDY AIMS

Discrepancies can occur between the histopathological findings from forceps biopsy and endoscopic mucosal resection (EMR), and occasionally in embarrassing cases tumorous tissue is not found at EMR. The aim of the present study was to evaluate the clinical, endoscopic, and histological features of gastric tumors in patients with pathololgically negative findings at EMR.

PATIENTS AND METHODS

We retrospectively reviewed data from all patients with gastric tumor treated with EMR or endoscopic submucosal dissection (ESD) between August 1999 and April 2007 at our institution, and enrolled into the study patients with no tumor tissue found at mucosal resection. Their biopsy and EMR specimen slides were reviewed by a single pathologist. Patient characteristics, including demographic and clinical features, and the endoscopic appearance of mucosal lesions were evaluated.

RESULTS

Out of 633 patients treated with EMR or ESD, 20 patients (3.2 %) were included. The mean +/- SD maximal dimension of the mucosal lesions was 6.40 +/- 2.19 mm (range 3 - 10). Mean number of forceps biopsy fragments was 3.80 +/- 1.96 and mean sampling ratio was 2.08 +/- 1.07 mm/fragment. Before resection, histological findings from forceps biopsy were: 13 low grade dysplasias (65.0 %), 2 high grade dysplasias (10.0 %), and 5 intramucosal carcinomas (25.0 %).

CONCLUSIONS

In the case of pathologically negative findings at EMR, tumors might have been small enough to have been removed by the previous forceps biopsy. However, the possibility of sampling error or of a different location should be considered. Furthermore, appropriate communication between endoscopists and pathologists is essential.

SLC11A1 gene polymorphisms in Korean patients with Behçet's disease

OBJECTIVE

To investigate the potential susceptibility to the solute carrier family 11 member 1 (SLC11A1) gene polymorphisms of Korean patients with Behçet's disease (BD).

METHODS

Ninety-nine patients with BD and 98 controls were recruited. Analyses of three polymorphisms of the SLC11A1 gene [the 5'-promoter (GT)n, D543N and A318V] were performed, either by denaturing high-performance liquid chromatography for D543N and A318V or by using automatic DNA sequencing for the (GT)n. The genotypes and alleles between patients with BD and the controls were compared using the chi2 test and Yate's correction test.

RESULTS

No significant differences were found in the distribution of genotypes and alleles of the (GT)n polymorphism between BD patients and the controls. However, subjects with the allele 3 or the genotype allele 3/allele 3 of this polymorphism had a significantly lower risk of developing BD than those without this allele or genotype [allele: p = 0.029, pc = 0.039, odds ratio (OR) = 0.60, 95% confidence interval (CI) 0.37-0.95; genotype: p = 0.036, pc = 0.048, OR = 0.54, 95% CI 0.31-0.96]. In addition, the distributions of genotypes and alleles of D543N were similar between BD patients and controls (p>0.05). In the case of A318V, all of the BD patients and controls had a wild-type genotype.

CONCLUSION

The allele 3 and the genotype allele 3/allele 3 of the 5'-promoter (GT)n in the SLC11A1 gene may have a protective effect for the development of BD in the Korean population. Further studies in other populations are required to confirm our results.

Nonexponential London penetration depth of FeAs-based superconducting RFeAsO(0.9)F(0.1) (R = La, Nd) single crystals

The superconducting penetration depth lambda(T) has been measured in RFeAsO(0.9)F(0.1) (R = La, Nd) single crystals (R-1111). In Nd-1111, we find an upturn in lambda(T) upon cooling and attribute it to the paramagnetism of the Nd ions, similar to the case of the electron-doped cuprate Nd-Ce-Cu-O. After the correction for paramagnetism, the London penetration depth variation is found to follow a power-law behavior, Deltalambda_{L}(T) proportional, variantT;{2} at low temperatures. The same T2 variation of lambda(T) was found in nonmagnetic La-1111 crystals. Analysis of the superfluid density and of penetration depth anisotropy over the full temperature range is consistent with two-gap superconductivity. Based on this and on our previous work, we conclude that both the RFeAsO (1111) and BaFe(2)As(2) (122) families of pnictide superconductors exhibit unconventional two-gap superconductivity.

Observation of the doubly cabibbo-suppressed decay D_{s};{+}-->K;{+}K;{+}pi;{-}

We report the first observation of the doubly Cabibbo-suppressed decay D_{s};{+}-->K;{+}K;{+}pi;{-} using 605 fb;{-1} of data collected with the Belle detector at the KEKB asymmetric-energy e;{+}e;{-} collider. The branching ratio with respect to its Cabibbo-favored counterpart B(D_{s};{+}-->K;{+}K;{+}pi;{-})/B(D_{s};{+}-->K;{+}K;{-}pi;{+}) is (0.229+/-0.028+/-0.012)%, where the first uncertainty is statistical and the second is systematic. We also report a significantly improved measurement of the doubly Cabibbo-suppressed decay D;{+}-->K;{+}pi;{+}pi;{-}, with a branching ratio B(D;{+}-->K;{+}pi;{+}pi;{-})/B(D;{+}-->K;{-}pi;{+}pi;{+})=(0.569+/-0.018+/-0.014)%.

Effect of ABCA1 variant on atherogenic dyslipidaemia in patients with Type 2 diabetes treated with rosiglitazone

AIMS

To investigate the effect of two common ATP-binding cassette transporter 1 (ABCA1) polymorphisms (rs4149263 and rs2020927) on atherogenic dyslipidaemia in Korean Type 2 diabetic patients who were treated with rosiglitazone.

PATIENTS AND METHODS

Two hundred and fifty-six patients with Type 2 diabetes who had never previously received peroxisome proliferator-activated receptor gamma (PPAR-gamma) agonists or lipid-lowering treatment were treated with 4 mg of rosiglitazone daily for 12 weeks without any adjustment to their glucose-lowering regimen. The primary outcome was the change in atherogenic index of plasma (AIP), calculated as log [triglyceride (mmol/l)/high-density lipoprotein cholesterol (mmol/l)], before and after rosiglitazone treatment. The effect of rosiglitazone on the change in AIP was compared across the ABCA1 single nucleotide polymorphisms (SNPs) rs41429263 and rs2020927.

RESULTS

Before adjustment, the change in AIP at 12 weeks was significantly different across the rs4149263 genotypes [median (interquartile range): -0.05 (-0.21, 0.09) for TT; 0.02 (-0.09, 0.17) for TC; and 0.11 (0.03, 0.25) for CC; P = 0.003], but not across the rs2020927 [-0.04 (-0.18, 0.10) for TT; 0.03 (-0.17, 0.15) for TC; and -0.03 (-0.13, 0.10) for CC; P = 0.401]. After controlling for age, gender and duration of diabetes, the presence of the C-allele was significantly associated with an increase in AIP by 0.13 [95% confidence interval (CI), 0.04-0.21; P = 0.003]. This association did not change significantly when body mass index and pretreatment metabolic parameters were additionally controlled for (the change in AIP: 0.14; 95% CI, 0.04-0.24; P = 0.007).

CONCLUSIONS

The ABCA1 SNP rs4149263 may be associated with the change in atherogenic lipid profile in Type 2 diabetes treated with rosiglitazone.

Degree of conversion of dual-cured resin cement light-cured through three fibre posts within human root canals: an ex vivo study

AIM

To evaluate the degree of conversion of one dual-cured resin cement light-cured through three fibre posts within extracted human teeth.

METHODOLOGY

Fifteen mandibular premolars were root filled and then divided into three groups. Variolink II was light-cured through the posts (LP, D.T. Light-Post; PP, FRC Postec Plus; SP, Snowpost) within the root canal. The degree of conversion was obtained at 1 mm intervals in 9 mm-deep longitudinally sectioned root canals using an optical microscope connected to an FTIR spectrophotometer (n = 10). The light transmission of each post tested was also examined using UV-Vis spectroscopy. Data were analysed using ANOVA and Tukey's test (alpha = 0.05).

RESULTS

The LP and PP posts revealed a light transmission of 10.2% and 7.7%, respectively, whereas the SP post exhibited a significantly lower value of 0.5%. The degree of conversion mean value ranged from 32.78% to 69.73% depending on the depth and type of post. For all the groups, there were significant decreases in the degree of conversion values for the middle region when compared with those for the cervical region (P < 0.05). Except at a depth of 1 mm, the SP group consistently exhibited significantly lower degree of conversion values than the other groups (P < 0.05). The linear regression analysis revealed a strong correlation between the light transmission of the posts and the overall degree of conversion value for each group (R(2) = 0.9888).

CONCLUSIONS

The decrease in the degree of conversion for Variolink II relative to the depth was dependent on the light transmission capacity of the posts tested.