Table 1. Frequency of micronucleated cells (MNC) and other nuclear alterations (karyorrhexis, pyknosis and karyolysis) in orthodontic patients undergoing X-ray exposure.

Groups	MNC (%)		Other nuclear alterations* (%)
	No. of individuals	Mean ± SD	No. of individuals	Mean ± SD
Prior to X-ray exposure	18	0.2 ± 0.1	18	8.5 ± 3.2
After X-ray exposure	18	0.2 ± 0.1	18	14.4 ± 4.8†

^*Karyorrhexis, pyknosis and karyolysis

^†P < 0.05 when compared to individuals prior to X-ray exposure