Abstract
I investigated the clinical date of 122 traumatized anterior primary teeth of 92 children treated in Ichinose Pediatric Dental Office that developed pulp canal obliteration. After trauma, pulp canal obliteration was observed most frequently after 6 months～1 year by X-ray examinations. Under the observation there was no clinical anomaly in 97 teeth and there were clinical anomalies in 25 teeth. The most frequent anomaly was internal resorption that showed rapid progress without consciousness and the rapid and progressive internal resorption caused tooth fracture and pulp necrosis. Internal resorptions found early were treated very well by pulpectomy. Another anomaly was pulp necrosis without internal resorption and intervention of eruption of permanent teeth. There are some cases of early loss of primary teeth and disturbed eruption of permanent teeth, so we should observe anterior primary teeth with pulp canal obliteration up to the time when the permanent teeth erupt.
