BACKGROUND AND AIM: The retained primary tooth (RPT) is a tooth that remains beyond its exfoliation time, which can cause some problems. This study aimed to evaluate the prevalence of RPT in unusual ages in Larestan, a city in Fars Province, southern Iran. METHODS: In this cross-sectional population-based study (April-Oct...

Explaining altruistic cooperation is one of the greatest challenges faced by sociologists, economists, and evolutionary biologists. The problem is determining why an individual would carry out a costly behavior that benefits another. Possible solutions to this problem include kinship, repeated interactions, and policing. Another solution that has recently received much attention is the threat o...

8 Chapter

Background: One of the most important epidemiologic indices for the assessment and measurement of dental caries is the Decayed, Missing, and Filled Teeth (DMFT) index which is used as an important criterion for the evaluation of the oral and dental health status of individuals. Therefore, the present study was conducted to determine DMFT6 (DMFT of the first permanent molar) index and the relate...

We survey the recent applications and developments of sieve methods related to discrete groups, especially in the case of infinite index subgroups of arithmetic groups.