Objectives: The aims of this study were to evaluate changes in the position of the upper and lower premolars and second molars after first permanent molars "FPMs" extraction, compare the changes in the position of the upper and lower teeth, evaluate the over eruption of the upper FPMs in case of extraction of the lower one, and evaluate the midline shift in a unilateral extraction cases. Materials: Fifty female patients with age range 8-10 (mean age 8.9±0.9) years had one to four FPMs extracted due to severe caries. Each case was followed up for two years after extraction. Where the sample was ended by 43 patients only. The angular and millimetric changes were documented by panoramic radiographs. Over eruption and midline shift were observed clinically. Results: Both the upper and lower premolars showed distal tipping. However the lower tipped more than the upper. Also the lower second premolar showed more distal tipping than the lower first premolar .The lower second molar showed more mesial tipping than the upper one which moved more bodily. There were no over eruption of upper second molar or midline shift. Conclusion: Extraction of the FPMs severely affected by caries is a good treatment alternative. Favorable spontaneous space closure by adjacent teeth could be expected without any intervention, if it is extracted prior to the eruption of the second molar.