The Sample includes children who are randomly selected by the R4 electronic file system in the pediatric dentistry specialty clinics at King Abdulaziz University Hospital (KAUH). A total of 2100 pediatric screening had been registered between April 2013 and November 2013 .These files will be checked for the eligible age in the study which is 5-9 years. Then, the inclusion and exclusion criteria will be checked, and the patients will be selected by systemic random sample.