Zahra Abdolalian, Mohammad Rafeie, Ahmad Reza Baghestani, Mohamad Amin Pourhosseingholi, Tahoura Daneshvar,
Volume 19, Issue 9 (12-2016)
Abstract
Abstract
Background: 4cure models are a model to analyze survival data that these models exist for long term survivors. Cure models are a special type of survival model where it is assumed that there are a proportion of subjects who had never event, thus, survival curve will eventually reach a plateau. Therefore, standard survival models are not appropriate because they do not account for the possibility of cure.The aim of the present research is to apply non-mixture cure model to analyze survival of patients with colorectal cancer.
Materials and Methods: We studied 232 patients with colorectal cancer who were visited and treated at Taleghani Hospital Research Center for Gastroenterology and Liver Disease in Tehran. These patients were diagnosed from 1987 to 2012 and followed up until 2013. The Effect of age, gender, family history, body mass index and site of infection were studied. Kaplan-Meier and Non-Mixture cure Model were used for analzing data.
Results: The ten-year survival rate after diagnosis in the studied patients was 64 % .A total of 60 (25.8 %) deaths due to colorectal cancer were observed. The mean of age at the time of diagnosis was 51.6 years. Based on non-mixed cure model, the rangs of age was 45-65 years old and BMI were significant.
Conclusion: When the population is divided into two groups (susceptible and non- susceptible individuals), using Cox semi-parametric model is not appropriate. Therefore, we should use cure models.
Forough Khodadadnejad, Majid Akbari, Fateme Abdolalian, Mahboube Daneshvar, Behzad Ahmadi, Zahra Zahraei,
Volume 24, Issue 3 (August & September 2021)
Abstract
Background and Aim: The success of endodontic treatment depends on the complete elimination of pathogenic bacteria inside the root canal. Enterococcus faecalis, a gram-positive, pathogenic, and anaerobic cocci, are the primary etiology of root canal infection in treated and untreated teeth and are highly associated with endodontic treatment failure. This study aimed to compare the antimicrobial activity of Sodium hypochlorite 2.5%, microemulsion of Myrtus 10%, and microemulsion of Thyme 0.6% on the E. faecalis after root canal filling.
Methods & Materials: In this experimental study, 25 extracted single canal human anterior teeth were collected, and their crowns were cut. Then after washing and cleaning, and filling, the sterilization was done using an autoclave. Then, except 5 teeth (negative control group), the teeth were smeared with E. faecalis and then divided into 5 groups randomly represented the irrigation by Sodium hypochlorite 2.5%, microemulsion of Myrtus 10%, and microemulsion of Thyme 0.6%, with a positive control group and negative control group. The teeth were filled with gutta-percha and then incubated in an incubator for 90 days at a temperature of 37°C. Finally, the comparison of CFU in the groups due to abnormal data distribution was performed using the Kruskal-Wallis test.
Ethical Considerations: The Ethics Committee of Arak University of Medical Sciences approved this study (Code: IR.ARAKMU.REC.1398.297).
Results: According to the results of this study, the correlation between the groups of cultured teeth was not significant(P>0.05). The specimens washed with microemulsion of the Thyme 0.6% had the highest positive number of cultures; the specimens washed by Sodium hypochlorite 2.5% had the lowest number of cultures.
Conclusion: This study showed that no statistically significant difference exists in their antimicrobial activity after root canal therapy after the use of different wash solutions.
