Simulation of condylar growth in the cat with pulsating electromagnetic currents

Orthodontists have been, and are, interested in influencing facial growth, specifically, mandibular growth. The purpose of this investigation is to enhance condylar growth by means of electric stimulation. Eight growing cats were bilaterally condylotomized and unilaterally at random received electric stimulation. Before the condylotomy bonemarkers were implanted in the zygomatic process and above the condylotomy site. The condylotomy effectively separated the head of the condyle from the body of the mandible, thus unloading the head. After 5 weeks, implant separation indicated increased condylar growth on the treated side of all eight cats. Histologically, the treated condyles of six cats were different from the controls in that the hypertrophic zone was irregular and vascularization increased. The treated condyle showed significantly more bonemarker separation than the control condyle. On average, the treated condyle showed 1.24 mm more separation than the control (p = 0.001 by the paired sample t test).