Assessing revascularization of avulsed permanent maxillary incisors by laser Doppler flowmetry

Laser Doppler flowmetry, or LDF, is a noninvasive method used to assess pulpal blood flow, or PBF. Dental avulsion is associated with loss of pulpal sensitivity. The authors conducted this study to assess whether LDF could be used to detect revascularization of replanted teeth.

The authors used LDF to assess the PBF values of avulsed permanent maxillary incisors treated using replantation and splinting in 17 subjects. They took measurements at four sessions: on the day of splint removal and at 12 weeks, 24 weeks and 36 weeks after splint removal. Five vital control teeth and five nonvital control teeth were used to assess the background signal. At 36 weeks, the authors determined clinically and radiographically whether revascularization had occurred.

LDF readings correctly predicted the pulp status in 88.2 percent of the readings. Of the readings for vital teeth, 100 percent were correct, and of the readings for nonvital teeth, 80 percent were correct. Univariate analysis of variance demonstrated that in revascularized teeth, the PBF value increased significantly from splint removal to week 12 after splint removal and from week 24 to week 36 after splint removal. In the teeth that failed to revascularize, the PBF value dropped significantly from week 24 to week 36 after splint removal.

The results of this study suggest that LDF accurately diagnoses revascularization of avulsed maxillary incisors after replantation and splinting.

LDF may become useful in detecting revascularization much earlier than standard sensitivity tests.