Thymoquinone accelerates new bone formation in the rapid maxillary expansion procedure.

OBJECTIVE The aim of this study was to evaluate the effect of systemic thymoquinone (TQ) in a rat rapid maxillary expansion (RME) study. DESIGN Thirty-two Wistar albino rats were divided into 4 equal groups: only-expansion (OE), expansion plus TQ (TQ1 group, TQ given to the rats during their nursery phase and during the expansion and retention period), expansion plus TQ (TQ2 group, TQ given to the rats only during the retention period), and control group (no procedure done). Expansion appliances were placed on the maxillary incisors of all animals for 5days. The appliance was deactivated during the 12day retention period. The rats were sacrificed at the end of the retention period. Histomorphometric evaluation was carried out in order to compare the number of osteoclasts, osteoblasts, and capillaries, as well as the intensities of inflammatory cells, and new bone formation amongst the groups. RESULTS New bone formation, number of capillaries and the ratio of intensities of inflammatory cells in maxillary sutures was higher in the TQ groups than in the other groups. Statistical analysis also demonstrated that osteoblast and osteoclast numbers were also highest in the TQ1 group. CONCLUSION Histomorphometric analysis demonstrated that systemic use of thymoquinone may be effective in accelerating new bone formation in the RME procedure and that TQ may be beneficial in preventing relapse following the RME procedure.