Retention and Patient Satisfaction of Conventional Over Simplified Non-Balanced Maxillary Removable Complete Dentures.

AIM: Insufficient evidence is available in quantifying the retention between simplified and conventional non-balanced dentures. The aim of the study was to quantify and compare the maxillary denture retention and patient satisfaction between conventional and simplified removable non-balanced complete dentures. METHOD: This randomized clinical trial recruited 44 patients (n=22) with definitive criteria. Simplified and conventional non-balanced complete dentures were fabricated for the intervention groups. The denture retention of maxillary complete dentures was assessed with a dynamometer and patient satisfaction with a visual analogue scale. The mean retention of maxillary denture and satisfaction were recorded at 0-,3-, and 6 - month intervals. The data were statistically analyzed. (α=.05). RESULTS: The mean ±SD of retention for conventional denture at 0, 3, and 6 months by dynamometer ranged from 122 ± 1.64 N to 121 ± 1.57 N and 111 ±1.45N to 110±1.97 N for the simplified denture. The mean ±SD of visual analogue score varied between 9.45±0.35 to 7.19± 0.69 for conventional dentures and 8.00 ±1.39 to 6.81±0.82 for simplified dentures. The repeated ANOVA, t-test and post-hoc Bonferroni revealed statistically significant differences between the two types of denture. (P⟨.05) Conclusion: Numerical retention and satisfaction were higher in conventional non-balanced dentures than simplified dentures.

Cultural and linguistic disparities in dental utilisation in New South Wales, Australia.

OBJECTIVE: To examine the patterns and predictors of dental utilisation in culturally and linguistically diverse (CALD) and non-CALD groups in New South Wales. DESIGN: Secondary analysis of the 2013 and 2015 NSW Adult Population Health Survey (n=24,707). MAIN OUTCOME: Dental utilisation, defined as a dental visit within the last 12 months. CALD groups were defined using country of birth and language. Andersen's theoretical model was used. Chi-square test and multivariate logistic regression analysis adjusted for potential confounding. Sample weights adjusted for sampling design. RESULTS: Most (69%) of the population were Australian born; 20% spoke a language other than English at home. Dental utilisation was 58.9% and 63.9% for CALD and non-CALD groups respectively. The foreign-born non-English speaking group had the highest level of education (60%) but lower levels of dental utilisation (OR:0.81, CI 0.69-0.94) than all groups. Australian born non-English speakers had similar levels of dental utilisation to the reference group (OR:1.27, CI 0.99-1.63). CONCLUSION: There are significant disparities in dental care utilisation among CALD populations. Foreign born, non-English speaking CALD migrants, and people experiencing socioeconomic disadvantage, are at greatest risk of inadequate dental utilisation. Furthermore, the combination of predisposing factors, language and cultural barriers compound disparities in oral health care utilisation. This data highlights the need for oral healthcare services that are sensitive to population needs, to reduce disparities among CALD communities residing in NSW.

Effect of Dual-tasking on Visual and Auditory Simple Reaction Times.

Visual and auditory simple reaction times were measured in Sri Lankan young adults to see the effect of dual-tasking on reaction time. Reaction times were measured using a reaction time program in a computer. Subjects responded to stimuli by pressing the spacebar with their dominant index finger. Visual and auditory simple reaction times (ms) in males (mean ± SD) were 293.5 ± 42.4, 302.2 ± 41.9 respectively. In females respective values were 315.1 ± 55.5, 313.1 ± 45. Males had statistically significant faster reaction times (p < 0.05) than females. The type of stimuli had no statistically significant effect (p > 0.05) within the same sex. Dual-tasking significantly increases (p < 0.05) both reaction times in both sexes. In females, dual-tasking affects simple auditory reaction time significantly more than simple visual reaction time (p < 0.05).

Lung function parameters of healthy Sri Lankan Tamil young adults.

OBJECTIVES: To establish reference norms of lung function parameters for healthy Sri Lankan Tamil young adults. DESIGN AND SETTING: Cross sectional study of Tamil students at the Faculty of Medicine, Jaffna. MEASUREMENTS: Healthy non smoking students of Sri Lankan Tamil ethnic group were enrolled. Age, height, weight, BMI and spirometric measurements (Micro Quark) were recorded in 267 participants (137 females and 130 males). RESULTS: Height was significantly correlated with (p<0.05) all the lung function parameters except FEV1%, PEFR and MEF75 in males. Prediction equations were derived by regression analysis based on the height as an independent variable. Predicted lung function values for a particular age and height were lower than values predicted for Pakistanis, Kelatanese Malaysians and eastern Indians. The values were comparable to south Indians in Madras. Our FVC values of males and VC of females were closer to Sri Lankan Sinhalese. FEV1 and FEF25-75 in males were slightly higher and FVC, FEV1 and FEF25-75 in females were slightly lower in Tamils. When mean values were compared, these parameters were significantly higher in Tamil males (p<0.001) and significantly lower in Tamil females (p<0.001). CONCLUSIONS: These values will be useful in interpreting lung function parameters of the particular age group as there are no published norms for Sri Lankan Tamils. However, our study sample was confined to medical students of 20-28 years which may explain the differences with Sinhalese.

Iliac crest angle: a novel sonographic parameter for the prediction of Down syndrome risk during the second trimester of pregnancy.

OBJECTIVES: To validate a new sonographic technique for the display and measurement of fetal iliac crest angle (ICA), and to determine the relative contribution of standardized fetal pelvic measurements for estimating risk of Down syndrome during the second trimester of pregnancy. METHODS: Three-dimensional ultrasonography of the fetal pelvis was performed during a second-trimester scan for genetic amniocentesis. A coronal view of the 'virtual pelvis' was obtained by applying a maximum intensity projection algorithm to visualize both iliac wings. Two different ICAs were measured from a coronal projection of the fetal pelvis (ICA-coronal 1 and ICA-coronal 2); the latter approach relied on using ischial tuberosities as reference landmarks. Next, a coronal projection of the fetal pelvis was rotated to demonstrate a rendered view of the axial fetal pelvis. Axial inner (ICA-inner), middle (ICA-middle) and outer (ICA-outer) ICAs were measured. The maximum anterior iliac distance measurement was defined as the widest separation between the most anterior points of the rendered iliac crests. The reproducibility of each ICA method was analyzed using Bland-Altman statistics. Simple and multiple logistic regression analysis determined the relative contribution of each parameter as a prenatal predictor of Down syndrome. RESULTS: Ninety-four normal fetuses and 19 fetuses with Down syndrome were examined. The ICA-middle and ICA-coronal 2 parameters were the most reproducible angle measurements. The mean +/- SD ICA-middle measurement for fetuses with Down syndrome was significantly greater than that for normal subjects (94.5 +/- 9.8 degrees vs. 83.1 +/- 6.5 degrees ; P < 0.001). The mean +/- SD ICA-coronal 2 angle measurement for fetuses with Down syndrome was slightly greater than that for normal subjects (57.9 +/- 5.5 degrees vs. 51.9 +/- 7.1 degrees ; P = 0.0014). A multiple logistic regression model including ICA-middle and ICA-coronal 2 provided a predictive ability of 88.1% based on the area under the receiver-operating characteristics curve. This combination had a sensitivity of 94.4% for a false-positive rate of 5% in the detection of Down syndrome. CONCLUSIONS: Standardized iliac crest measurements of the fetal pelvis can be used to identify some fetuses at risk for trisomy 21 during the second trimester of pregnancy.

Impact of copper on in-vitro biomineralization, drug release efficacy and antimicrobial properties of bioactive glasses.

This study highlights the incorporation of copper in the bioactive glasses (BAG) network that greatly influences the morphological, structural and biological properties. By increasing the copper incorporation in BAG, increment in cell volume was obtained from XRD patterns, and concomitantly, dominant phosphate bands and latent silica bands were observed by FT-IR and Raman spectroscopic results. The Cu addition also affected particle appearance to vary from spherical to cluster-like cubes in 1.5% and 2.5% copper-doped BAG. Due to the mesoporous network 1.5% and 2.5% copper-doped BAG showed enhanced release of anti-inflammatory drugs such as Acetaminophen (ACE) and Ibuprofen (IBU) in which, the drug release profiles showed best fit with kinetic models of First order, Korsmeyar-Peppas and Higuchi. Copper doping influences the lattice of BAG, as a result morphology and porosity varied, which regulates the ionic dissolution, hence, prompting bioactivity was perceived from 1.5% and 2.5% copper-doped bioactive glasses (Cu-BGs). Moreover, 2.5% Cu-BG and 1.5% Cu-BG showed highest rate of ROS detection, as well as improved antimicrobial activity. This study established that up to certain proportion of copper incorporation in BAG network, potentially enhances the biomineralization and turns the morphology towards minimal size with mesoporous nature. Due to the abundance in oral microbial exposure, copper amplifies the superior antimicrobial properties, and Cu-BGs act as a drug carrier to load ACE and IBU, which potentially up-regulate the healing properties in dental application.

Effect of a low-lying placenta on delivery outcome.

OBJECTIVES: To evaluate delivery outcome in pregnancies with a low-lying placenta (within 2 cm of, but not covering, the internal os) that had been identified within 4 weeks of delivery. We examined the likelihood of a vaginal delivery and investigated the clinical significance of the placental edge to internal os measurement. METHODS: A retrospective chart review was performed for singleton pregnancies delivering in the third trimester with a low-lying placenta identified within 4 weeks of delivery. Outcome variables included type of delivery, maternal and neonatal hemoglobin levels, and umbilical artery pH levels. RESULTS: Eighty-six patients met the study criteria of a low-lying placenta identified within 4 weeks of delivery. Forty-five of these patients were allowed to labor and, of these, 29 (64.4%) delivered vaginally. The vaginal delivery rate was 76.5% in patients with a placenta to cervical os distance of 1-2 cm, significantly greater than the rate of 27.3% in patients in whom the placenta was within 1 cm of the cervix (P = 0.0085). A maternal hemoglobin level below 8.0 g/dL was the most common morbidity associated with low-lying placenta. Analysis of morbidity observed did not clearly favor either elective Cesarean delivery or attempted vaginal delivery. CONCLUSIONS: In this retrospective study, most laboring patients with a low-lying placenta were able to have a vaginal delivery with limited morbidity. The likelihood of a vaginal delivery was greater with increased placenta to cervical os distance. Further studies are needed to determine the clinical significance of the placenta to cervical os distance and the interval from scan to delivery.

Fetal growth parameters and birth weight: their relationship to neonatal body composition.

OBJECTIVES: The main goal was to investigate the relationship between prenatal sonographic parameters and birth weight in predicting neonatal body composition. METHODS: Standard fetal biometry and soft tissue parameters were assessed prospectively in third-trimester pregnancies using three-dimensional ultrasonography. Growth parameters included biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), mid-thigh circumference and femoral diaphysis length (FDL). Soft tissue parameters included fractional arm volume (AVol) and fractional thigh volume (TVol) that were derived from 50% of the humeral or femoral diaphysis lengths, respectively. Percentage of neonatal body fat (%BF) was determined within 48 h of delivery using a pediatric air displacement plethysmography system based on principles of whole-body densitometry. Correlation and stepwise multiple linear regression analyses were performed with potential prenatal predictors and %BF as the outcome variable. RESULTS: Eighty-seven neonates were studied with a mean +/- SD %BF of 10.6 +/- 4.6%. TVol had the greatest correlation with newborn %BF of all single-parameter models. This parameter alone explained 46.1% of the variability in %BF and the best stepwise multiple linear regression model was: %BF = 0.129 (TVol) - 1.03933 (P < 0.001). Birth weight similarly explained 44.7% of the variation in %BF. AC and estimated fetal weight (EFW) accounted for only 24.8% and 30.4% of the variance in %BF, respectively. Skeletal growth parameters, such as FDL (14.2%), HC (7.9%) and BPD (4.0%), contributed the least towards explaining the variance in %BF. CONCLUSIONS: During the late third trimester of pregnancy %BF is most highly correlated with TVol. Similar to actual birth weight, this soft tissue parameter accounts for a significant improvement in explaining the variation in neonatal %BF compared with fetal AC or EFW alone.

Fractional limb volume--a soft tissue parameter of fetal body composition: validation, technical considerations and normal ranges during pregnancy.

OBJECTIVES: The main goals were to provide normal reference ranges for fractional limb volume as a new index of generalized fetal nutritional status, to evaluate the reproducibility of fractional fetal limb volume measurements during the second and third trimesters of pregnancy, and to demonstrate technical considerations for this technique. METHODS: This was a prospective, cross-sectional study of gravid women during mid to late pregnancy. Fractional limb volumes were based on either 50% of humeral or femoral diaphysis length. Each partial volume was subdivided into five equidistant slices that were centered along the mid-arm or mid-thigh. Slices were traced manually to obtain fractional arm (AVol) or fractional thigh (TVol) volume. Reproducibility studies were performed, using Bland-Altman plots, to assess blinded interobserver and intraobserver measurement bias and agreement. Selected images were chosen to demonstrate technical factors for the acquisition and analysis of these parameters. Reference charts were established to describe normal ranges for AVol and TVol. RESULTS: Three hundred and eighty-seven subjects were scanned to include 380 AVol (range, 1.1-68.3 mL) and 378 TVol (range 2.0-163.2 mL) measurements between 18.0 and 42.1 weeks' menstrual age. No gender differences were found in these soft tissue measurements (AVol, P = 0.90; TVol, P = 0.91; Mann-Whitney test). Intraobserver mean bias +/- SD and 95% limits of agreement (LOA) for fractional limb volumes were: 2.2 +/- 4.2% (95% LOA, - 6.0 to 10.5%) for AVol and 2.0 +/- 4.2% (95% LOA, - 6.3 to 10.3%) for TVol. Interobserver bias and agreement were - 1.9 +/- 4.9% (95% LOA, - 11.6 to 7.8%) for AVol and - 2.0 +/- 5.4% (95% LOA, - 12.5 to 8.6%) for TVol. Technical factors were related to image optimization, transducer pressure, fetal movement, soft tissue compression and amniotic fluid volume. CONCLUSIONS: Fractional limb volume assessment may improve the detection and monitoring of malnourished fetuses because this soft tissue parameter can be obtained quickly and reproducibly during mid to late pregnancy. Careful attention should be placed on technical factors that can potentially affect optimal acquisition and analysis of these volume measurements.

New fetal weight estimation models using fractional limb volume.

OBJECTIVES: The main goal of this study was to determine the accuracy and precision of new fetal weight estimation models, based on fractional limb volume and conventional two-dimensional (2D) sonographic measurements during the second and third trimesters of pregnancy. METHODS: A prospective cross-sectional study of 271 fetuses was performed using three-dimensional ultrasonography to extract standard measurements-biparietal diameter (BPD), abdominal circumference (AC) and femoral diaphysis length (FDL)-plus fractional arm volume (AVol) and fractional thigh volume (TVol) within 4 days of delivery. Weighted multiple linear regression analysis was used to develop 'modified Hadlock' models and new models using transformed predictors that included soft tissue parameters for estimating birth weight. Estimated and observed birth weights were compared using mean percent difference (systematic weight estimation error) and the SD of the percent differences (random weight estimation error). The proportion of newborns with estimated birth weight within 5 or 10% of actual birth weight were compared using McNemar's test. RESULTS: Birth weights in the study group ranged from 235 to 5790 g, with equal proportions of male and female infants. Six new fetal weight estimation models were compared with the results for modified Hadlock models with sample-specific coefficients. All the new models were very accurate, with mean percent differences that were not significantly different from zero. Model 3 (which used the natural logarithms of BPD, AC and AVol) and Model 6 (which used the natural logarithms of BPD, AC and TVol) provided the most precise weight estimations (random error = 6.6% of actual birth weight) as compared with 8.5% for the best original Hadlock model and 7.6% for a modified Hadlock model using sample-specific coefficients. Model 5 (which used the natural logarithms of AC and TVol) classified an additional 9.1% and 8.3% of the fetuses within 5% and 10% of actual birth weight and Model 6 classified an additional 7.3% and 4.1% of infants within 5% and 10% of actual birth weight. CONCLUSION: The precision of fetal weight estimation can be improved by adding fractional limb volume measurements to conventional 2D biometry. New models that consider fractional limb volume may offer novel insight into the contribution of soft tissue development to weight estimation.

Holographic analysis of the initial canine displacement produced by four different retraction springs.

OBJECTIVES: To estimate and compare the magnitude and direction of initial displacement of the canine produced by four different canine retraction springs. MATERIALS AND METHODS: A freshly macerated mandible was used as an experimental model. First premolars were extracted, and strap-up was done with a 0.018 inch Roth Preadjusted Edgewise System (3M Unitek, Monrovia, Calif). The canine was subjected to loads of 4 oz, 5 oz, and 6 oz, each applied by four different canine retraction springs, that is, closed coil spring, open coil spring, PG spring, and T-loop retraction spring. The magnitude and direction of the initial displacement of the canine were studied by means of double-exposure interferometry. RESULTS: The PG spring produced the highest initial displacement for a given force among the force systems used, followed by open coil, closed coil, and T-loop. Maximum tipping was observed with the open coil spring, followed by the PG spring, the closed coil spring, and the T-spring. CONCLUSION: The T-loop may be preferred whenever minimal tipping is performed. The PG spring may be preferred over other springs whenever a higher magnitude of displacement is desired. Closed coil springs may be preferred whenever a reasonable magnitude of displacement is required and reasonable tipping is allowed.

Ultrasonication-assisted fabrication of hierarchical architectures of copper oxide/zinc antimonate nanocomposites based supercapacitor electrode materials.

In this work, a new nanohybrid consisting of copper oxide and zinc antimonate was designed using ultrasonication assisted homogenous magnetic stirring approach and investigated their performance as an electrode material for supercapacitors. Combination of the duo could enhance the electrical conductivity and charge storage capacity of whole nanostructured electrode, which is very much essential for supercapacitor application. Primarily, the prepared nanohybrid electrode material was investigated through XRD, FT-IR, FE-SEM, HR-TEM, UV-DRS, PL and XPS to determine their structural, morphological, optical and compositional characteristics. Thereafter, the electrochemical properties of the nanohybrid electrode were investigated using CV, GCD and EIS studies in 1.0 M KOH solution. The fabricated nanohybrid electrode material exhibits exceptional electrochemical performance by delivering maximum specific capacitance of 257.14 F g-1 at a current density of 12.5 A g-1. The nanocomposite showed high cycling stability of 102.0% even after 2000 cycles at a current density of 10.0 A g-1. These exceptional electrochemical characteristics of CuO/ZnSb2O6 nanocomposites are due to their dual nanorod morphology, influence of ultrasonication on non-aggregated nanocomposite formation, presence of more number of electrochemical active sites, and their synergistic interactions. The obtained results confirmed that CuO/ZnSb2O6 nanocomposites could be a potential candidate as electrode materials for supercapacitors.

Sonochemistry-assisted fabrication of 1D-ZnSb2O6@2D-MoS2 nanostructures: A synergistic energy storage material for supercapacitors.

In this work, a novel nanohybrid composing of molybdenum disulphide nanosheets and zinc antimonate nanorods was fabricated using ultrasonication assisted homogenous magnetic stirring approach and investigated their electrochemical performance as an electrode material for supercapacitors. First and foremost, the structural, vibrational, morphological, optical and chemical compositional characteristics of the fabricated nanohybrid electrode material were investigated. Subsequently, the electrochemical properties of the nanohybrid electrode were explored using CV, GCD and EIS studies in 1.0 M KOH solution. The fabricated nanohybrid electrode material exhibited tremendous electrochemical performance by distributing maximum specific capacitance of 469.28 F g-1 at a current density of 5.0 A g-1 with high cycling stability of 102.0% even after 2000 cycles at a current density of 10.0 A g-1. These exceptional electrochemical characteristics of MoS2/ZnSb2O6 nanocomposites are ascribed to the influence of ultrasonication on non-aggregated nanocomposite formation, existence of more number of electrochemical active sites and synergistic interactions between two different nanostructures. The acquired results confirmed that MoS2/ZnSb2O6 nanocomposites could be a prospective and electrochemically active candidate as electrode materials for supercapacitors.

Cleidocranial dysplasia: a case report.

Cleidocranial dysplasias is an autosomal dominant disorder that presents with skeletal dysplasia. The dental manifestations are mainly delayed exfoliation of primary teeth and delayed eruption of permanent teeth, with multiple impacted supernumeraries. This report addresses the complex nature of the treatment modalities. In our patient, surgical exposure of unerupted teeth was done with orthodontic traction. Post-surgical follow-up was uneventful.

Myelodysplastic syndrome at a large tertiary care community hospital: analysis according to the international prognostic scoring system.

The outcome of patients diagnosed myelodysplastic syndromes (MDS) between 1990 and 1997 from William Beaumont Hospital (WBH) was analyzed according to the International Prognostic Scoring System (IPSS) risk categorization. A retrospective study of 195 MDS patients wa s performed. Seventy-nine patients with MDS, in whom a karyotype was obtained and with an adequate follow-up were included in the final analysis. Cases of proliferative CMML (WBC > 12x10(9)/l) were excluded from the study. The overall median survival was 3.1 years, and median survival stratified by IPSS was 3.4, 4.1 and 0.5 years for the INT-1, INT-2 and high risk group and not yet reached for the low risk group. The overall survival by IPSS subcategorization were 6.88, 5.29, 5.30 and 2.12 years for the low, INT-1, INT-2, and high risk groups respectively. Cytogenetics were significant in predicting the overall survival. The IPSS score stratified patients into risk categories for development of AML. The risk of development into AML was 8, 8, 33 and 54% for the low, INT-1, INT-2 and high risk groups, respectively. We conclude that IPSS score can be useful in predicting survival and AML evolution in some MDS patients.

Use of the activated partial thromboplastin time for heparin monitoring.

The objectives of the present study were to evaluate the relationship between heparin concentration and activated partial thromboplastin time (aPTT) results, define a heparin concentration-derived therapeutic range for each aPTT instrument, compare aPTT- and heparin concentration-guided dosage adjustment decisions, and compare laboratory- and bedside aPTT-guided decisions. In phase 1, 102 blood samples were analyzed for bedside and laboratory aPTTs and heparin concentration (used to establish aPTT therapeutic range). In phase 2, 100 samples were analyzed in the same manner. Correlations for aPTT compared with heparin ranged from 0.36 to 0.82. Dosage adjustment decisions guided by the aPTT agreed with those based on heparin concentration 63% to 80% of the time. Laboratory and bedside aPTT dosage adjustment decisions agreed 59% to 68% of the time. The correlation of aPTT with heparin concentration and agreement between aPTT- and heparin-guided decisions vary with the aPTT instrument. Decisions guided by laboratory aPTT results often disagree with decisions guided by bedside aPTT results.

Different heparin lots: Does it matter?

OBJECTIVE: To assess the impact of heparin lot on the correlation between heparin concentration and activated partial thromboplastin time (aPTT), the aPTT therapeutic range, and the heparin level. DESIGN: Retrospective analysis of data from 2 previous studies. SETTING: Teaching institution with 929 beds. PATIENTS: Ninety-five patients receiving heparin with 5 different lots (study 1) and 35 patients receiving heparin with 3 different lots (study 2). MAIN OUTCOME MEASURES: Laboratory-based aPTT and heparin level by anti-factor Xa analysis. Standard heparin curves were created for each lot. Each patient's heparin level was determined off each standard curve. RESULTS: Correlations between heparin concentration and aPTT ranged from 0.87 to 0.89 (study 1) and 0.86 to 0.87 (study 2). Slopes of regression lines were not significantly different. Therapeutic ranges generated from lot-specific heparin levels were similar. Average bias in heparin levels from varying lots ranged from 0.005 to 0.036 units/mL. CONCLUSIONS: The recommendation to reevaluate the aPTT therapeutic range with each new lot of heparin requires further evaluation.

Ascaris lumbricoides in the lacrimal passage.

Ascariasis is caused by the roundworm, Ascaris lumbricoides. We report an additional case of live Ascaris lumbricoides removed from the lacrimal puncta of a 10-year-old boy.

Dosimetric comparison between bone marrow sparing intensity-modulated radiation therapy and conventional techniques in the treatment of cervical cancer: a retrospective study.

PURPOSE: To investigate enlargement of prostate volume by edema during brachytherapy seed implantation and develop a nomogram model to calculate air-kerma strength (AKS) required for implantation of the enlarged transient prostatic volume. MATERIALS AND METHODS: The prostate volume was measured prior and after seed implantation using trans-rectal ultrasound imaging in the operating room to obtain volume enlargement. A nomogram model was developed that calculates AKS required for implantation of the enlarged transient prostate volume with optimal dose coverage. RESULTS: The measured prostate enlargement in this study was up to 60% of the initial volume. The effective prostatic volume enlargement was calculated for three isotopes: 125I, 103Pd and 131Cs. The effective volume enlargement for 125I implants was relatively small (< 10%) because of its long half-life. For 103Pd and 131Cs with short half-lives, additional AKS up to 20% and 30%, respectively, might be required to provide appropriate dose coverage of possible enlarged prostatic volumes. CONCLUSIONS: Prostate volume enlargement should be considered to obtain optimal dose coverage particularly for short half-life isotopes such as 131Cs and 103Pd. The nomogram model developed in this work provides the AKS required for implants with a wide range of prostatic volume enlargements (5-100%) for three isotopes. KEYWORDS: prostate brachytherapy, nomogram, airkerma strength, edema, volume enlargement.

Forward versus inverse planning in oropharyngeal cancer: A comparative study using physical and biological indices.

CONTEXT: Possible benefits of inverse planning. AIMS: To analyze possible benefits of inverse planning intensity modulated radiation therapy (IMRT) over field-in-field 3D conformal radiation therapy (FIF-3DCRT) and to evaluate the differences if any, between low (6 Million Volts) and high energy (15 Million Volts) IMRT plans. MATERIALS AND METHODS: Ten patients with squamous cell carcinoma of oropharynx, previously treated with 6 MV step and shoot IMRT were studied. V100, V33, V66 , mean dose and normal tissue complication probabilities (NTCP) were evaluated for parotid glands. Maximum dose and NTCP were the parameters for spinal cord. STATISTICAL ANALYSIS USED: A two-tailed t-test was applied to analyze statistical significance between the different techniques. RESULTS: For combined parotid gland, a reduction of 4.374 Gy, 9.343 Gy and 7.883 Gy were achieved for D100, D66 and D33, respectively in 6 MV-IMRT when compared with FIF-3DCRT. Spinal cord sparing was better in 6 MV-IMRT (40.963 ± 2.650), with an average reduction of maximum spinal cord dose by 7.355 Gy from that using the FIF-3DCRT technique. The uncomplicated tumor control probabilities values were higher in IMRT plans thus leading to a possibility of dose escalation. CONCLUSIONS: Though low-energy IMRT is the preferred choice for treatment of oropharyngeal cancers, FIF-3DCRT must be given due consideration as a second choice for its well established advantages over traditional conventioan technique.