Effect of micro-pulsed electricity on experimental tooth movement.

The purpose of this study was to determine whether a micro-pulsed electrical potential on the tooth surface could induce effective remodeling of the alveolar bone and enhance tooth movement. Twenty-eight cats were divided into 4 groups of 7 animals each for 1, 4, 7, and 14 days of treatment, respectively. A 60 gram orthodontic force was applied to distally tip the maxillary canines. In addition, the left canine only was subjected to a one hertz square wave form of 6 volts which induced a current of about 10 microA. Tooth movement and the amount of newly formed bone for the control and experimental sides were compared statistically using the Student's t test. Histochemical observations were also carried out. The results indicated that when electrical stimulus was applied to the surface of the canines in addition to mechanical force: 1) The periodontal tissue was affected. 2) The teeth moved more rapidly. 3) Wider areas of bone deposition and larger amounts of newly formed bone were observed on the tension side, and the amount of this newly formed bone increased with time. 4) More osteoblasts were observed on the tension side. 5) More tartrate-resistant acid phosphatase (TRACP) positive mononuclear and multinuclear cells were seen on the compression side. These results indicate that micro-pulsed electrical stimulation might play a role in the efficient remodeling of alveolar bone, and in inducing more rapid tooth movement.