Clinical evaluation of two materials in the restoration of abfraction lesions

Aim: To evaluate the clinical performance of a composite resin (CR) and a resin-modified glassionomer cement (RMGIC) for the treatment of abfraction lesions. Methods: Thirty patients with abfraction lesions in at least two premolar teeth were selected and invited to participate in this study. All restorations were made within the same clinical time frame. One tooth was restored with CR Z100TM (3M, St. Paul, MN, USA), and the other was restored with RMGIC VitremerTM (3M). The restorations were assessed immediately and 1, 6 and 12 months after the restoration, using modified US Public Health Service (USPHS) criteria: marginal integrity, marginal discoloration, wear, retention, secondary caries and hypersensitivity. The statistical analysis was based on Friedman ANOVA test and Mann-Whitney test, considering p<0.05 for statistical significance. Results: Both materials demonstrated satisfactory clinical performance after one year. In the individual analysis of each material, there was a significant difference (p<0.05) in the criteria marginal integrity and wear, for both CR and RMGIC. RMGIC exhibited more damage one year after the restoration. Comparing both materials, it was found a significant difference only for marginal discoloration, while the RMGIC restorations showed the worst prognosis after a year of evaluation. There was no significant difference in the number of retentions, caries or hypersensitivity between CR and RMGIC. Conclusions: It was concluded that CR exhibited the best clinical performance according to the cost-effectiveness and evaluation criteria used in this study.

Monitoring of specific activities of long-lived radioactive elements along the Mini- Okoro/Oginigba Creek, Port Harcourt

Presence and concentrations of radionuclides could be as a result of natural and human activities. This study examined the associations and differences among soil, sediment and water specific activities of long-lived radioactive element (LLRE). Gamma spectroscopy was used to measure the concentration of the LLRE along the Mini Okoro/Oginigba Creek, Port Harcourt. Specific activities of three selected LLRE were derived. Correlation analysis was carried out to examine associations among the specific activities across different substrates. A strong and a significant negative correlation exists between the specific activities of Water 40K and Soil 232Th (r =-0.721, p<0.05); Water 238U and Soil 238U (r = -0.717, p<0.05) and Water 40K and Sediment 238U (r=-0.69, p<0.05). Comparison using Mann-Whitney U test shows that, soil and sediment are similar in their specific activities with Z values of -0.408, -1.209 and -1.021 (p > 0.05) for 40K, 232Th and 238U respectively. The concentration of solid samples (soil and sediment) is different from the liquid (water) samples. These associations can be attributed to some specific underlying factors. And in other to understand them there is need for more studies.

Influence of ultrasonic activation in association with different final irrigants on intracanal smear layer removal

Aim: To evaluate the influence of ultrasonic activation (US) with different irrigant regimens in smear layer removal. Methods: One hundred bovine incisors were instrumented and divided into ten groups (n=10) according to final irrigation protocols: distilled water (DW); DW+US; 17% EDTA; QMix; 10% citric acid; 37% phosphoric acid; 17% EDTA+US; QMix+US; 10% citric acid+US; 37% phosphoric acid+US. The samples were then submitted to scanning electron microscopy where a score system was used to evaluate the images and effectiveness of proposed treatments. The data were statistically analyzed by Kruskal-Wallis and Mann-Whitney U tests for intergroup comparisons as well as the Wilcoxon and Friedman tests for intragroup comparisons at 5% significance level. Results: In the cervical third, groups 17% EDTA, QMix, 10% citric acid, 17% EDTA+US, QMix+US and 10% citric acid+US were more effective in smear layer removal (p<0.05); in the middle third, groups 17% EDTA+US and QMix+US were more effective in smear layer removal (p<0.05); in the apical third, groups 17% EDTA,17% EDTA+US and QMix+US were more effective in smear layer removal (p<0.05). Conclusions: US can aid 17% EDTA and QMix in smear layer removal at the middle third and QMix at the apical third, contributing to the cleaning of root canal system.

Pediatric Intussusception in Northern Iran: Comparison of Recurrent With Non-Recurrent Cases

Background: Intussusception represents as the invagination of a part of the intestine into itself and is the most common cause of intestinal obstruction in infants and children between 6 months to 3-years-old. Objectives: The objective of this study was to determine the recurrence rate and predisposing factors of recurrent intussusception. Patients and Methods: The medical records of children aged less than 13-years-old with confirmed intussusception who underwent reduction at a tertiary academic care in northern Iran (Mazandran), from 2001 to 2013 were reviewed. Data were extracted and recurrence rate was determined. The two groups were compared by chi square, Fisher, Mann-Whitney and t-test. Diagnosed cases of intussusception consisted of 237 children. Results: Average age of the patients was 19.57 ± 19.43 months with a peak of 3 to 30 months. Male to female ratio was 1.65 and this increased by aging. Recurrence rate was 16% (38 cases). 87 (36.7%) underwent surgery. These were mainly children under one year old. In 71% (40) of episodes recurrence occurred 1 to 7 times within 6 months. The recurrence occurred in 29 (23.5%) children in whom a first reduction was achieved with barium enema (BE) and 5 (5.7%) children who had an operative reduction (P < 0.001) in the first episode. Pathological leading points (PLPs) were observed in 5 cases; 2.6% in recurrence group versus 2% in non-recurrence group (P = 0.91). Three patients had intestinal polyp, 2 patient’s lymphoma and Mackle’s diverticulum. Age (P = 0.77) and sex (P = 0.38) showed no difference between the two groups. PLPs were observed in 1.4% of children aged 3 months to 5 years. This was 13.3%, in older children (P = 0.02). Conclusions: The recurrence of intussusception was related to the method of treatment in the first episode and it was 5-fold higher in children with BE than in operative reduction. Recurrent intussusceptions were not associated with PLPs, they were more idiopathic.