Material and Methods: A cross sectional study was conducted of 375 children aged 6-12 years. The sample was divided into two groups according their ages, Group A, which included 150 children with age ranging between 6 to 8 years old. While group B which involved 225 children with age ranged from 9 to 12 years old. The diagnosis of caries was based on the World Health Organization (WHO) criteria. The collected data was analyzed using SPSS, version 16 and Chi-square test was used.

Results: In group A, the frequency of carious FPMs were (186 teeth; 12.4%), whereas sounds were (414 teeth; 27.6%). However in group B, the frequency of sound FPMs were (411 teeth; 27.4%), while carious were (489 teeth; 32.6%). A significant difference was found between the two age groups regarding caries incidence (P< 0.0001). The incidence of carious molars in group B was higher in the lower left jaw (9.4%).

Conclusion: Significant differences were found between two groups regarding caries incidence of FPMs. However, the highest rate of carious FPMs was found in group B, thus caries incidences of FPMs is increased as age increased, A significant difference (P< 0.05) was found between two groups regarding the distributions of caries in the different segment of dental arch.

Recommendation: FPMs are very important teeth for maintaining integrity of the dental arches. However, the incidences of caries in FPMs were increased with the age. Therefore, it is recommended that it necessary to pay careful preventive strategies involving fissure sealant, home care and fluoride applications. In addition, promote the educational programmers’ for parents.