Background: Gastroesophageal reflux disease, is a quite prevalent gastrointestinal disease, among which gastric content (excluding the air) returns into the oral cavity. Many 0ral manifestations related t0 this disease include tooth wear, dental caries also changes in salivary flow rate and pH. This study was conducted among gastroesophageal reflux disease patients in order to assess tooth wear in relation to salivary flow rate and pH among these patients and the effect of gastroesophageal reflux disease duration on this relation. Materials and methods: One hundred patients participate in this cross-sectional study for both genders and having an age range of 20-40 years old, patients had been endoscopically identified as having gastroesophageal reflux disease using the classification of Los Angeles (LA), who were attending the Gastroenterology and Hepatology Teaching Hospital in Baghdad. and divided into two groups: group A with grade severity mucosal breakage not longer than 5 mm and Group B with grade severity mucosal breakage more than 5 mm long, Smith and Knight (1984) tooth wear index criteria were used for the assessment of tooth wear. For measurement of salivary flow rate and pH, saliva sample (unstimulated) had been collected. Results: Of the entire sample (90%) were having tooth wear. Tooth wear was higher in grade B severity than in grade A severity among patients with gastroesophageal reflux disease duration of two years or less, while it was higher in grade A than in grade B among patients with a duration of more than two years but all these results were statistically non-significant. Salivary flow rate and pH showed a non-significant reduction with increasing gastroesophageal reflux disease severity for both of groups concerning disease duration. The correlation of total tooth wear with salivary flow rate and pH was a significantly weak negative correlation in grade A, while a nonsignificant weak negative correlation in grade B. Conclusions: The findings of the present study concluded that patients with gastroesophageal reflux disease recorded a high occurrence of tooth wear and there was a negative correlation of tooth wear with salivary flow rate and pH among patients with gastroesophageal reflux disease.
In this paper, we estimate the survival function for the patients of lung cancer using different nonparametric estimation methods depending on sample from complete real data which describe the duration of survivor for patients who suffer from the lung cancer based on diagnosis of disease or the enter of patients in a hospital for period of two years (starting with 2012 to the end of 2013). Comparisons between the mentioned estimation methods has been performed using statistical indicator mean squares error, concluding that the survival function for the lung cancer by using shrinkage method is the best
In this paper,we estimate the parameters and related probability functions, survival function, cumulative distribution function , hazard function(failure rate) and failure (death) probability function(pdf) for two parameters Birnbaum-Saunders distribution which is fitting the complete data for the patients of lymph glands cancer. Estimating the parameters (shape and scale) using (maximum likelihood , regression quantile and shrinkage) methods and then compute the value of mentioned related probability functions depending on sample from real data which describe the duration of survivor for patients who suffer from the lymph glands cancer based on diagnosis of disease or the inter of patients in a hospital for perio
... Show More
We have presented the distribution of the exponentiated expanded power function (EEPF) with four parameters, where this distribution was created by the exponentiated expanded method created by the scientist Gupta to expand the exponential distribution by adding a new shape parameter to the cumulative function of the distribution, resulting in a new distribution, and this method is characterized by obtaining a distribution that belongs for the exponential family. We also obtained a function of survival rate and failure rate for this distribution, where some mathematical properties were derived, then we used the method of maximum likelihood (ML) and method least squares developed (LSD)
... Show More