ABSTRACT
There are many unknown systemic and local factors influencing tooth growth and development. Likely, tooth eruption may be under such influence as well. Despite delayed tooth eruption, studies on early tooth eruption are very scarce. Therefore, this study was conducted in order to evaluate the relationship between intelligence quotient [IQ] and early tooth eruption in normal children [with no disease or disorder]. By using study criteria, 44 children were recruited after oral examination of 652 children [337 boys and 315 girls]. Oral examination was conducted by one dentist using plastic disposable mirror, under day light. The Raven's test was taken blindly under standard conditions for all subjects by a psychologist. [Case] subjects were defined as individuals who had partially or fully erupted molars earlier than the expected normal time. [Control] subjects were similar to [cases] but without erupted molars. Statistical analysis was conducted using student T-test. The intelligence test was performed on 44 subjects consisted of 22 boys [IT'case] and 1 T'control]] and 22 girls [11 [case] and 11 [control]]. IQ in two sexes did not have significant difference [P<0.05]. But the mean IQ difference between [case] and [control] groups was about 11 points that was statically significance [P<0.01]. Healthy children with early first permanent molar eruptions, have higher IQ compared to their peers [P<0.01]. This criterion may be used to identify high IQ children for provision of special care and training for faster advancement of individual and society