Cytokines in crevicular fluid and orthodontic tooth movement

Orthodontic force stimulates eNOS and iNOS in rat osteocytes

Mechanosensitive osteocytes are essential for bone remodeling. Nitric oxide, an important regulator of bone remodeling, is produced by osteocytes through the activity of constitutive endothelial nitric oxide synthase (eNOS) or inducible nitric oxide synthase (iNOS). We hypothesized that these enzymes regulate the tissue response to orthodontic force, and therefore we investigated eNOS and iNOS expression in osteocytes during orthodontic force application. The upper rat molars were moved mesially by NiTi coil springs (10 cN, 120 hrs) in a split-mouth design. Immunohistochemical staining revealed that, in the tension area, eNOS-positive osteocytes increased from 24 hrs on, while iNOS-positive osteocytes remained largely constant. In the compression area, iNOS-positive osteocytes increased after 6 hrs, while eNOS- positive osteocytes increased after 24 hrs. This suggests that eNOS mediates bone formation in the tension area, while iNOS mediates inflammation-induced bone resorption in the compression area. Both eNOS and iNOS seem to be important regulators of bone remodeling during orthodontic force application.

Tenoxicam controls pain without altering orthodontic movement of maxillary canines

OBJECTIVES

To study the efficacy of tenoxicam for pain control, its potential for preemptive analgesia, and its influence on the orthodontic movement of upper canine teeth.

DESIGN

This was a randomized controlled double-blind cross-over study. The patients were divided into three groups. Two groups received tenoxicam in daily doses of 20 mg orally for 3 days. Group A received the first dose of the drug before orthodontic activation and group B, just afterwards. Group C (control) received a placebo for 3 days. All groups had access to 750 mg of paracetamol up to four times a day. Three orthodontic activations were performed at 30-day intervals. Each patient belonged to two different groups. Pain intensity was assessed using a descriptive Pain Scale and a Visual Analog Scale.

SETTING AND SAMPLE POPULATION

Private clinic; 36 patients undergoing bilateral canine tooth retraction.

RESULTS

The statistical analysis did not show any difference in movement between the active groups and the control at any time. There was no statistical difference between the groups that received tenoxicam. Pain intensity in these groups was lower than in the placebo group. The difference in pain intensity between the active groups and the control was greatest at the assessment made 12 h after activation and it tended to zero, 72 h after activation.

CONCLUSIONS

Tenoxicam did not influence orthodontic movement of the upper canines. It was effective for pain control and did not present any preemptive analgesic effect.